2009 Transmission and Distribution Annual Planning Report

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Disclaimer

This document is published by Western Power as an information service. It does not purport to contain all the information that may be necessary to enable a person to assess whether to pursue a particular investment. It contains only general information and should not be relied upon as a substitute for independent research and professional advice. Western Power makes no representations or warranty as to the accuracy, reliability, completeness or suitability for particular purposes of the information in this document.

Copyright Notice

All rights reserved. This entire publication is subject to the laws of copyright and intellectual property rights. This publication may not be resold or reproduced without the prior permission of Western Power, except as permitted under the Copyright Act 1968.

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Preface

Welcome to the 2009 Transmission and Distribution Annual Planning Report. This report outlines Western Power’s network development plans based on its second Access Arrangement (AA2) submission as of 31 January 2009, which considers forecast growth in electricity demand from existing and prospective customers and expected generation requirements.

We trust this Annual Planning Report will give you a greater insight into our planning process and long term goals for the network.

Our objective is to serve the community and industry through prudent investment in the network to provide sustainable, reliable electricity and secure, timely connection.

Please note that this report contains general information and should not be relied upon as a substitute for independent market research.

We value your feedback regarding the level and format of detail provided about specific projects, and any additional information you believe we need to take into account.

We look forward to working with you.

Mark de Laeter General Manager Customer Services Division. Western Power.

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Contents

Disclaimer Preface Executive summary Invitation to provide feedback 1 Introduction 13 1.1 Purpose of this document 13 1.2 Interaction with the Statement of Opportunities report 13 1.3 Role of Western Power 14 1.4 Approval process 15 2 Network development planning process 17 2.1 Network development analysis 18 2.2 Transmission network planning standards 18 2.2.1 Bulk transmission network 18 2.2.2 Sub transmission network 19 2.2.3 Radial networks 19 2.2.4 Substations 19 2.3 Distribution network planning standards 20 2.3.1 CBD 20 2.3.2 Metropolitan 20 2.3.3 Rural 21 3 Network planning assumptions 23 3.1 Developing and applying electricity demand forecasts 23 3.1.1 Typical drivers of load growth 23 3.1.2 Western Power’s load forecasting methodology 23 3.1.3 Managing weather sensitivity risks in demand forecasting 24 3.1.4 Review of load forecasting practice 24 3.2 Location of new generation 25 3.2.1 Southern generation development scenario 26 3.2.2 Northern generation development scenario 26 3.2.3 Metropolitan generation development scenario 27 3.2.4 Eastern generation development scenario 28 4 Description of load areas 31 5 Projects (approved, committed or commissioned) 35 5.1 Bulk transmission 37 5.1.1 Approved projects – bulk transmission 38 5.1.2 Regulatory Test submissions – bulk transmission 39 5.1.3 Future development projects – bulk transmission 40 5.1.4 Future outlook – bulk transmission 41 5.2 Northern Terminal 43 5.2.1 Approved projects – Northern Terminal 44 5.2.2 Regulatory Test submissions – Northern Terminal 45 5.2.3 Future development projects – Northern Terminal 47 5.2.4 Future outlook – Northern Terminal 48 5.3 Muja 51 5.3.1 Approved projects – Muja 52 5.3.2 Regulatory Test submissions – Muja 52 5.3.3 Future development projects – Muja 53 5.3.4 Future outlook – Muja 53

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5.4 Kwinana 57 5.4.1 Approved projects – Kwinana 58 5.4.2 Regulatory Test submissions – Kwinana 59 5.4.3 Future development projects – Kwinana 60 5.4.4 Future outlook – Kwinana 61 5.5 Cannington 63 5.5.1 Approved projects – Cannington 63 5.5.2 Regulatory Test submissions – Cannington 66 5.5.3 Future development projects – Cannington 66 5.5.4 Future outlook – Cannington 67 5.6 Bunbury 69 5.6.1 Approved projects – Bunbury 70 5.6.2 Regulatory Test submissions – Bunbury 71 5.6.3 Future development projects – Bunbury 72 5.6.4 Future outlook – Bunbury 73 5.7 Western Terminal 75 5.7.1 Approved projects – Western Terminal 76 5.7.2 Regulatory Test submissions – Western Terminal 77 5.7.3 Future development projects – Western Terminal 78 5.7.4 Future outlook – Western Terminal 78 5.8 East Perth & CBD 81 5.8.1 Approved projects – East Perth & CBD 82 5.8.2 Regulatory Test submissions – East Perth & CBD 83 5.8.3 Future development projects – East Perth & CBD 85 5.8.4 Future outlook – East Perth & CBD 86 5.9 Southern Terminal 87 5.9.1 Approved projects – Southern Terminal 88 5.9.2 Regulatory Test submissions – Southern Terminal 90 5.9.3 Future development projects – Southern Terminal 91 5.9.4 Future outlook – Southern Terminal 92 5.10 South Fremantle 95 5.10.1 Approved projects – South Fremantle 96 5.10.2 Regulatory Test submissions – South Fremantle 97 5.10.3 Future development projects – South Fremantle 98 5.10.4 Future outlook – South Fremantle 99 5.11 East Country 101 5.11.1 Approved projects – East Country 102 5.11.2 Regulatory Test submissions – East Country 102 5.11.3 Future development projects – East Country 103 5.11.4 Future outlook projects – East Country 104 5.12 Eastern Goldfields 105 5.12.1 Approved projects – Eastern Goldfields 106 5.12.2 Regulatory Test submissions – Eastern Goldfields 107 5.12.3 Future development projects – Eastern Goldfields 107 5.12.4 Future outlook – Eastern Goldfields 108 5.13 North Country 111 5.13.1 Approved projects – North Country 112 5.13.2 Regulatory Test submissions – North Country 113 5.13.3 Future development projects – North Country 114 5.13.4 Future outlook – North Country 115

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5.14 Guildford 117 5.14.1 Approved projects – Guildford 118 5.14.2 Regulatory Test submissions – Guildford 119 5.14.3 Future development projects – Guildford 120 5.14.4 Future outlook – Guildford 121

6 Other planning issues 123 6.1 Sustainability 123 6.1.1 Planning checklist 123 6.1.2 Environmental management 123 6.1.3 Stakeholder engagement 124 6.1.4 Environmental strategy 125 6.2 Communications network 127 6.2.1 Western Power communication technologies 127 6.2.2 Protection 127 6.2.3 SCADA (Supervisory Control and Data Acquisition) 127 6.2.4 Operations 127 6.2.5 Choice of bearer 129 6.3 State Underground Power Program (SUPP) 130 6.4 Reliability improvement program 131 6.5 Demand side management 133 6.6 Alternative generation 133

7 Abbreviations 135

8 Appendix A – Introduction to network issues 137 8.1 Planning and operating electricity networks 137 8.2 Faults on electricity networks 138 8.3 Meshed and radial networks 139 8.4 Peak demand, weather and diversity 139

9 Appendix B – Substation load forecasts 141

10 Appendix C – Estimated maximum short circuit levels 151

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Executive summary

The purpose of this document is to provide information regarding major planned developments in Western Power’s South West Interconnected System (SWIS). The document is written for existing and prospective network users and other interested parties, in keeping with Western Power’s policy and as required by Economic Regulatory Authority (ERA) guidelines.

Network development planning The network planning process is a continuous process one. As such, this Annual Planning Report (APR) is a snapshot of the constraints and network Western Power’s network development plans developments as they are currently understood. are based on regional forecasts of peak demand, assumptions about generation Network planning assumptions developments and a detailed understanding of the capacity of the existing network. These Three levels of demand forecasts are required assumptions are used for sophisticated network for network planning purposes: analysis that ensures each network element • A demand forecast for the bulk transmission satisfies a number of planning and technical system, which is broadly based on forecasts criteria. reported in the Independent Market For convenience, the network is divided into Operator’s 2008 Statement of Opportunities the bulk transmission network and 13 sub Report, and which allows peak network flows across the bulk transmission network to be transmission and distribution load areas. modelled; Each load area is studied in detail to ensure compliance with the relevant planning and • Demand forecasts for each substation, which technical criteria. Where there has been are developed by extrapolating previous significant changes in a particular area (perhaps substation and system peaks for each due to significant load growth or a new substation, and which allow peak power generator connecting), it will be re-assessed as flows across each substation element to be a matter of priority. modelled; and

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• Demand forecasts for each load area, which preferred reinforcement options or to propose allow peak power flows across the network any alternative option with regard to these elements in each load area to be modelled. projects. These forecasts are developed using the Major transmission and distribution projects bulk transmission and individual substation provided in this report are classified in the forecasts. following categories: In each case, the focus is on understanding • ‘Approved projects’ the most onerous conditions that will affect each network element. The most onerous - defined as any major project where operating condition for each load area is derived Western Power’s Board has approved from a combination of the demand at the time or is deemed very likely to approve a of system peak and local demand peaks, submitted business case. depending on the characteristics of that load • ‘Regulatory Test submissions’ area. - projects requiring a Regulatory Test to be The load forecasts used for network planning submitted within the next five years; are based on a 10% Probability of Exceedance: that is, the probability that Western Power’s - projects with forecast transmission peak demand forecast is likely to be exceeded budgets greater than $30 million or one year in every 10. distribution budgets greater than $10 million, or a combined transmission Scenario analysis has been performed based and distribution budget greater than on the ‘announced’ generation projects to $30 million. assess the impact on the network. The need for network development is highly sensitive to the • ‘Future development projects’ location and type of generation development. - major transmission and distribution Western Power is aware that some generation development projects that have not yet projects cannot be reflected in this public been submitted for approval; document. For this and other reasons, future - projects that do not require a Regulatory development plans may be materially different Test within the next five years; from those published here. - projects that still require detailed planning. Where prudent to do so, Western Power will seek to anticipate generation location decisions • ‘Future outlook’ and commence investment to ensure that the - long term development of the network; network can respond to market needs in a timely fashion. This investment will be subject - projects that are in the initial conception to, amongst other things, the regulatory regime, stages. access code and capital contributions policy. Sustainability Transmission and distribution Western Power has adopted a company wide projects sustainability policy articulating our commitment The major transmission and distribution to contribute to the challenges of sustainable projects for each load area are described in development. Western Power’s aim is to Chapter 5 of this Annual Planning Report (APR). undertake an ethical and sustainable works These projects represent Western Power’s program through the application of sustainable preferred network development approach assessment methodologies that underpin this given the available information at the time of policy. consideration. The Environment and Land Management The APR also provides an opportunity for the Branch (ELM) is responsible for managing the public to comment on any of Western Power’s community consultation process, obtaining

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environmental and planning approvals and Alternative generation negotiating land easements where required. Western Power is positioned to become an Communications network energy solutions business. We believe in creating a network that supports all types of Western Power is committed to providing a energy generation. robust, flexible communications network. The recently introduced regulatory and electricity Western Power welcomes enquiries and market framework places higher reliance on applications for the connection of generation available, accurate and timely data. Western from renewable energy sources. Power has correspondingly improved its design criteria to ensure: Invitation to provide feedback • high circuit availability; Western Power would welcome feedback • provision for redundant paths; on this Transmission and Distribution Annual Planning Report. • a fibre optic cabling based solution as the first preference; and Comments on this document should be sent to: • a suitable environment for communications Manager Network Planning & Development equipment. Western Power Corporation GPO Box L921, Perth WA 6842 State Underground Power Program Telephone: (08) 9326 6293 (SUPP) Facsimile: (08) 9218 5167 Western Power is continuing its commitment to Western Power would particularly like to hear having half the Perth metropolitan area serviced from parties who are considering investments by underground power by the year 2010. Each that, based on the information provided here, major residential project is funded jointly by the would appear to either: State Government, Western Power and by the relevant local government. • delay requirements for network development options; or Reliability improvement program • accelerate requirements for network development options. Western Power’s reliability improvement plan establishes solid and robust business rules Relevant information will be incorporated and processes for the effective, practical, cost in Western Power‘s planning process and effective and efficient delivery of reliable power reflected in future editions of the Annual to all Western Power customers. Planning Report.

Demand side management

Western Power considers alternate network solutions, including demand side management, for all reinforcement projects. This will improve the overall long term costs associated with supply of electricity.

Western Power is currently assessing an air conditioner direct load control trial in areas supplied by Nedlands zone substation and also Denmark and Walpole. It is anticipated that further demand side management trials will be implemented to establish the effectiveness of these initiatives.

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1 Introduction

The 2009 Transmission and Distribution Annual Planning Report (APR) describes Western Power’s major network development plans from 2009 to 2014.

This APR also provides an opportunity for the 1.1 Purpose of this document public to comment on any of Western Power’s The purpose of this document is to provide preferred reinforcement options or to propose existing and prospective network users and any alternative option with regard to any project other interested parties information on planned detailed in this report. developments on Western Power’s South-West The report is structured as follows: Interconnected System (SWIS). It also provides some background on Western Power’s planning • Chapter 1 introduces the purpose of this process. document, its interaction with the Statement This document aims to: of Opportunities report and Western Power’s role in the electricity market; • identify constraints on the transmission network likely to emerge in the next 10 years; • Chapter 2 describes Western Power’s planning process and standards; • provide advance information on the nature and location of network constraints; • Chapter 3 explains the key assumptions (namely demand and generation; forecasts) • discuss options for relieving each constraint including network and other options; and that underpin the network development plans reproduced here; • provide further details on the load forecast data used as the basis for this analysis. • Chapter 4 provides a description of the load areas within the Western Power network; This information should allow other parties to formulate and propose options to relieve the • Chapter 5 provides a description of the network constraints. These options may include ‘approved projects’, the ‘Regulatory Test local generation, demand side management submissions’, ‘network development (DSM) or other economic alternatives. projects’ and the ‘future outlook’ for each load area within Western Power’s South- Western Power publishes this document on West Interconnected System; an annual basis. Future versions will reflect the latest available (commercially non-sensitive) • Chapter 6 describes other network issues information, including feedback received on the relating to sustainability, communications and previous edition. network reliability; 1.2 Interaction with the Statement of • Appendix A provides a short introduction to Opportunities report network planning issues; This report complements the role of the 2008 • Appendix B details substation load forecasts; Statement of Opportunities report (SOO). While and the Statement of Opportunities focuses on the overall adequacy of generation capacity, • Appendix C details maximum three phase the focus of the APR is on the adequacy and single phase to earth short circuit levels. and development of the transmission and distribution network. The remainder of this introduction describes the purpose of this document, its interaction with Where applicable, the generation and demand the Statement of Opportunities report and the forecast information used in the preparation of role of Western Power. this APR has been largely based on the 2008

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Statement of Opportunities. Given the inherent Until recently, Western Power Corporation was complexity of the network planning process, it is an integrated energy company, which owned necessary to allow sufficient time for assimilating and operated the generation, transmission and relevant new or revised information in the distribution infrastructure in Western Australia. Statement of Opportunities to produce network On 1 April 2006, Western Power Corporation development outcomes that reflect any such was restructured into four new Government- information. As a consequence, publication of owned corporations: the APR follows the Statement of Opportunities. • Verve Energy, a generation corporation Network planning is based on the predicted responsible for power generation in the load growth throughout the SWIS. The SWIS; Independent Market Operator (IMO) publishes a forecast of maximum demand at 10% • Synergy, a retail corporation responsible for Probability of Exceedance (PoE), 50% PoE and the sale of electricity in the SWIS; 90% PoE. The overall forecast of maximum summer demand is shown in Figure 1. • Horizon Power, a regional power corporation responsible for electricity in all areas outside 1.3 Role of Western Power of the SWIS; and

Western Power is responsible for the • Western Power, a networks corporation safe, reliable and efficient distribution and responsible for the transport of electricity within the SWIS. transmission of electricity in the South- West Interconnected System (SWIS), which The SWIS contains more than 140 major spans from Albany to Kalbarri and across to substations, 6,000 km of transmission lines Kalgoorlie. Western Power connects electricity (operating at voltages of 66 kV and greater) to homes and businesses, and is responsible and more than 64,000 km of high voltage for maintaining and upgrading the electricity distribution lines (operating at 33 kV and lower). network.

Figure 1: SWIS Load History and IMO Forecast.

6500

6000

5500

5000

4500 MW 4000

3500

3000

2500

2000 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18 YEAR Load History 10% PoE Expected Growth 10% PoE High Growth 10% PoE Low Growth

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1.4 Approval process code promotes the economically efficient investment in, and operation of networks Western Power’s operations are guided by and services in Western Australia to promote regulations, codes and legislation that have competition. been developed by various regulatory bodies and the State Government, including the In accordance with the Network Access Code, Economic Regulation Authority (ERA), the Office Western Power operates under an access of Energy, Energy Safety (part of the Department arrangement which prescribes the terms and of Consumer Protection), and other bodies such conditions on which users can obtain access as the Environmental Protection Authority and to the SWIS. This access arrangement was WorkSafe. These regulations cover almost all approved by the ERA in April 2007. aspects of our operations, from performance In particular, the access arrangement includes targets and return on assets, through to the approved levels of capital expenditure for proper disposal of waste and the safety of each financial yesr. Western Power must also employees and the public. demonstrate, to the satisfaction of the ERA, that The Network Access Code 2004 establishes a its actual capital expenditure incurred is both framework for third party access to electricity prudent and efficient. transmission and distribution networks. This

Dual 330 kV transmission lines.

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2 Network development planning process

Western Power applies risk management principles when applying its network development planning process.

Western Power’s planning process is focussed • Asset management plans: The asset on balancing network costs against the impact management plans are based on condition of unreliable supply on its customers. The assessment of the network to ensure that process is applied within the planning and it will continue to provide reliable service. development framework, illustrated in Figure 2. Condition assessments drive the asset Western Power’s network investment strategy replacement component of the Network is developed through a number of contributing Investment Strategy. factors. These include: • Western Power’s commercial objectives: • Technical rules: Western Power has Western Power’s strategy is developed established a set of technical rules for in light of the various drivers illustrated in transmission and distribution performance Figure 2. The regulatory environment means standards for the network and technical Western Power’s capital expenditures requirements for plant connected to the need to satisfy the stringent requirements network. of the Electricity Networks Access Code. • Load and generation forecasts: Western It must also demonstrate that investments Power’s forecasts are based on projections are economically justifiable under the New of state economic growth, load history and Facilities Investment Test, and that possible customer connection enquiries. Western alternative options to major investments have Power also makes prudent assumptions been evaluated and considered as part of the about the development of generation Regulatory Test. projects.

Figure 2 Overview of network planning process.

Customer, stakeholder Regulatory Demand & generation & community expectations framework & codes requirements

Network performance & Sustainability WESTERN POWER’S condition (Reliability, & technology CUSTOMER VISION Quality, Safety) developments

Demand side Planning criteria Network investment strategy management opportunities

Technology plan Embedded Development options, generation consultation & APR forum Technical code opportunities

Load & Network generation Optimised, prioritised asset missions forecasts works program & plans

Project approvals, Funding submission Regulatory submission contracts, funding to government

IMPLEMENTATION

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These inputs are used in the network analysis • location and timing of major new loads or to ensure each element satisfies a number of load centres; and planning and technical criteria, so that: • rate of forecast network load growth. Long • each individual network element is operated term growth trends also determine the need within its design limits. This requires voltage for network augmentations. and power transfer for each asset to be assessed under a wide range of potential 2.2 Transmission network planning conditions, including for example modelling standards the effect of faults on the network. Failure Western Power develops its transmission to meet voltage design limits can result network in accordance with the Technical Rules, in malfunction or damage to customer approved by the ERA in April 2007. equipment, while exceeding power transfer limits creates potential safety hazards and Planning criteria for the transmission network reliability issues arising from the failure of are based on a risk analysis that takes into network equipment due to overloads; account: • the network can withstand credible faults • the size, extent and sensitivity of load or and unplanned outages. A fault is considered generation which may be affected; credible if it is considered likely given the • the physical location of various components prevailing circumstances. If there is a credible of the network and their exposure to damage fault or unplanned outage, all plant must risk; still operate within its design limits and the network must continue to deliver the required • the relative merits of other alternatives; and performance; • the efficient use of capital.

• quality of supply is maintained to the Generally, the transmission system is a appropriate standards. Quality of supply is a meshed network with a high proportion of term that embraces voltage, frequency and elements in service at any given time. The other technical aspects of power supply; transmission system is broadly divided into the • potential for future growth is adequately bulk transmission network, sub-transmission provided for, where economically viable to do networks, radial networks and substations. so, ensuring that Western Power’s electricity network does not impede economic 2.2.1 Bulk transmission network development; and The bulk transmission network operates at 330 • environmental impacts are responsibly and 132 kV. It consists of the power station managed. switchyards, major terminal switchyards and the 2.1 Network development analysis interconnecting transmission lines. The bulk transmission network is designed to The planning and operation of electricity withstand a single unplanned outage without networks must meet certain technical loss of load. It is also designed to withstand one requirements. There are various factors that will forced outage and one planned outage at 80% change power flows across the network, which of forecast peak load (assuming generation must be taken into account when planning and rescheduling after the first outage). operating the system, including: • changes in network configuration, either by The bulk transmission network requires this level construction of new elements or outages of of security given the high capacity of the bulk existing network elements; transmission network where outages may affect • location and timing of new generation many customers. sources impacts on thermal capacity, stability and fault performance, and thus the need for network augmentation;

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2.2.2 Sub transmission network Radial networks take into account analysis of network reliability, risk and economics. In a The sub transmission network operates at 132 radial network, back-up may be provided by and 66 kV. It consists of zone substations and other parts of the transmission network, the the interconnecting transmission lines. distribution network, local generation or not at The sub transmission network is generally all, depending on this analysis. designed to withstand a single unplanned It is not always economic to provide full outage without loss of load. redundancy on the radial networks due to the When there is more than one outage at the large line lengths, geographically dispersed same time, there may not be enough network loads and generally smaller loads (when capacity to meet all demand. Sometimes, there compared to metropolitan areas). may be limited back-up capacity available via the distribution network. 2.2.4 Substations

This broadly applies to the network supplying Substations interconnect the sub transmission urban areas in the Perth metropolitan region network with the distribution network. Each and major regional centres. These parts of the substation is designed to meet planning criteria network tend to be characterised by relatively that depend on the substation’s location and the high load densities and shorter transmission type of load it supplies: lines. • Substations in the Perth CBD are designed The Perth CBD has a higher level of security to provide the highest level of security. requiring continuous supply, following the events • Regional substations are designed to provide of two coincident transmission outages. the next highest level of security due to the long travelling times required before plant 2.2.3 Radial networks can be repaired or replaced, although there Radial networks operate at 220, 132 and 66 kV are some remote substations designed to and generally supply loads of less than 20 MW. provide a relatively low level of security. The 132 and 66 kV radial networks generally • Substations in the Perth metropolitan area supply regional townships in Western Australia’s south-west region. are designed to accept a higher level of risk of load shedding, as they are accessible for plant repairs or replacement. The designs of the various types of substations recognise the need to optimise security of supply and capital expenditure.

CBD substations are designed to withstand the failure of a single item of plant without any sustained loss of load. They are also designed to withstand the failure of either two items of plant or both transmission lines supplying a substation with only a temporary interruption to load.

Most regional substations are designed to withstand the failure of a single item of plant without sustained loss of any load. A small number of regional substations are designed to withstand the failure of a single item of plant with a small risk that up to 10% of the load may Rural transmission lines. need to be shed. This risk only applies for 1% of

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the time throughout a year and is based on the feeders. The loss of a network element will availability of suitable spares. generally lose supply to a number of customers, however Western Power attempts to reduce A small number of regional substations are not the impact by installing reclosers, sectionalisers, able to continue to supply load for a failure of fault indicators, load break switches and remote a single item of plant. These substations have control pole-top switches. usually been established for one customer where the customer has accepted the risk. If The distribution network is broadly divided into nearby loads then take the opportunity to be the CBD, Metropolitan and Rural areas. supplied by these substations, it is often not economic to provide higher supply security. 2.3.1. CBD

Most substations supplying the Perth The CBD distribution network is an open- metropolitan area are designed to withstand the meshed and remotely-switched design. failure of a single item of plant (about a one in This facilitates rapid restoration of supply to 20 year event), accepting that some load may healthy sections of the network after faults. In be shed, on a rotational basis, for up to nine addition, CBD zone substations automatically hours. In line with commercial objectives, since reconfigure feeders after the loss of step- down transformers. The total loss of a single- 1996, Western Power has accepted the risk of zone substation requires manual network short duration load shedding to maximise the reconfiguration to restore supplies within four utilisation of substation capacity. hours. CBD feeders are normally limited to 50% 2.3 Distribution network planning of their maximum rated capacity. This provides standards flexibility to remotely reconfigure the network and to restore load after a feeder outage. Western Power develops its distribution network in accordance with the Technical Rules, 2.3.2 Metropolitan published in April 2007. Metropolitan distribution networks are open- The distribution network is operated at voltages meshed networks with radial feeders and inter- of 33 kV, 22 kV, 11 kV, 6.6 kV and 415 V, and feeder ties that can be switched into service as is generally designed to operate through radial required. This moderate level of interconnection

Waikiki substation.

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between feeders and a planned maximum feeder loading of 80% allows for the transfer of load between feeders after a fault. In contrast to the CBD, this transfer of load may require a number of manual-switching operations.

This feeder arrangement minimises fault levels and simplifies technical and operational requirements. With multiple open points, improved supply restoration times are possible, although the initial loss of supply will still occur.

2.3.3 Rural

The distribution networks in rural areas are radial and are much longer than metropolitan feeders, with limited inter-feeder ties. As a result, supply restoration after a network fault takes longer. Some distribution feeders can be very long, with no interconnection to accelerate supply restoration.

Users requiring security of supply above the standard design philosophy will be provided with network back-up where practicable. However, on-site standby generation may be the only economic solution. Investment to provide additional security of supply is normally at the customer’s expense.

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3 Network planning assumptions

This chapter provides some background to the detailed planning assumptions used to manage the network.

The most common planning assumptions announcements of sizeable industrial loads relate to peak demand across the network and to come into operation over the next decade. location of new generation. These are described These loads are included in the base in section 3.1 and 3.2 respectively. assumptions when they can be considered as committed projects; and 3.1 Developing and applying • mining activity in regional areas and growth in electricity demand forecasts regional centres. In contrast to the Statement of Opportunities 3.1.2 Western Power’s load forecasting (SOO), which provides forecasts at the overall methodology system level, the network development planning process also requires forecasts for Three levels of demand forecasting are required each substation and terminal station. To then for network planning purposes. These include: determine augmentation needs, Western Power • demand forecast for the bulk transmission assesses network capability against electricity system, which is broadly based on the demand forecasts by: demand forecasts reported in the SOO, • direct comparison with each network and which allows peak network flows element’s thermal rating; and across the bulk transmission network to be • computer simulations to identify thermal, modelled. An overall load forecast for the voltage, stability and fault rating constraints. bulk transmission network is the sum of individual substation forecasts at the time of 3.1.1 Typical drivers of load growth the expected system peak load, corrected to match the demand forecasts reported in the In the SWIS, typical drivers of load growth SOO; include: • demand forecasts for each substation, which • penetration of air-conditioners. Recently, are developed by extrapolating previous increased residential air-conditioning has peaks for each substation, and which allow boosted electricity demand significantly. If peak power flows across each substation air-conditioner penetration grows further, element to be modelled. Western Power’s weather sensitivity is likely to increase forecasting methodology is based on strongly; statistical analysis of historic load information • new residential sub-divisions. There is rapid for every substation and terminal station. growth in new residential developments Expected block loads are added to these along the northern and southern coastal demand forecasts, as appropriate; and strip towards Two Rocks and Mandurah, as • demand forecasts for each load area, which detailed in the Metropolitan Development allow peak power flows across the network Program; elements in each load area to be modelled. • Urban Land Release Plans, released by the These forecasts are developed using the Western Australian Planning Commission bulk transmission forecasts and the individual available at www.wapc.wa.gov.au; substation forecasts.

• in-fill growth in older metropolitan suburbs, In each case, the focus is on understanding resulting in increased housing and hence the most onerous conditions that will affect increased load density; each network element. For example, the bulk • isolated larger customers such as shopping transmission network’s most onerous power centres and particular industrial/commercial flows are normally at the time of system peak. loads. There have been a number of An individual substation may have its peak

2009 Transmission and Distribution Annual Planning Report 24

load at a different time to the remainder of the The peak demand day has generally occurred network. Simply using load forecast for the time between the end of the summer school of system peak would potentially understate holidays and the middle of March. Over the the duty of each substation element and lead to past 50 years, the average highest maximum inadequate development plans. temperature each summer has been 41°C. The average of the highest minimum temperature The most onerous operating condition for each summer has been 26°C. each load area is derived from a combination of the demand at time of system peak and This average ‘hottest’ day is the basis of peak local demand peaks, depending on the demand projections and is known as the 50% characteristics of that load area. PoE. The variations that may occur on warmer or milder ‘hottest’ days are known as the 10% The forecasts produced by the Independent and 90% PoEs respectively. Market Operator (IMO) in July 2008 and the energy forecast, indicate that for the expected Western Power uses the 10% PoE in its economic growth scenario over the next 10 modelling. This provides an appropriate level years, peak demand is forecast to grow by of capacity within the network for the expected 4.5% annually, while energy consumption growth in electricity demand. is forecast to grow by 3.9% annually. This indicates that the peak load is growing at a 3.1.4 Review of load forecasting practice higher rate than the average load supplied Load forecasts are a critical input into the throughout the year. network planning and development process. Western Power’s network reinforcement plans 3.1.3 Managing weather sensitivity risks in and capital expenditure requirements are demand forecasting developed from load flow studies that depend The highest peak demand for the SWIS is on forecasts of load at the low voltage side generally mid-week after a consecutive string of of each individual substation’s transformer. hot and humid days with temperatures between The forecast loads with reactive power the high 30s and mid 40s, with hot and humid compensation removed are directly uploaded to conditions overnight. Western Power’s load flow model for performing load flow studies under contingency conditions In a hot summer, such as the summer of 1997, to identify network constraints. (where peak day temperatures reached a maximum of 44.5°C, minimum 29.0°C), peak This process enables the identification of demand was approximately 150 MW above that network constraints and the necessary network on an average summer peak day. augmentations to increase capacity in the SWIS network such that growth in peak electricity In contrast, during a mild summer, such as in demand can be catered for. 2002, (where peak day temperatures reached Given the fundamental importance of load a maximum of 36.3°C, minimum 21.5°C), peak forecasts to the electricity network development demand was approximately 100 MW below that process, that is, the ability to cater for peak of an average summer peak day. demand growth with prudent and timely capital To account for weather-related variation in expenditure, it is vitally important for Western forecasts, peak demand is expressed as PoE Power to continually improve its capability and values. Taking 50% PoE as an example, for excellence in the following areas: every 10 demand readings, on average five • understanding of anticipated load growth. readings would be over the 50% PoE value Demand growth can arise from the and five would be below the 50% PoE value. development of proposed large bulky Similarly, on average, one sample would be over loads such as new mining projects, the 10% PoE value and nine samples would be land developments, economic factors, below the 10% PoE value. population growth and other demographic

2009 Transmission and Distribution Annual Planning Report 25

factors. Western Power will be increasingly Western Power relies on proponents to more connected with industry and other provide details of projects early enough government agencies to ensure that the to be incorporated in scenario planning. anticipated needs of network users are However, there are a range of factors that adequately catered for in a timely and cost can change the feasibility, timing, size and effective manner; location of such projects. Moreover, in some • understanding the sensitivity of peak demand instances, proponents only provide details of to weather conditions. Weather conditions their intentions once the projects are nearly play a significant role in driving growth in committed, to minimise their commercial risk. peak demand primarily due to increased use of electricity for space cooling and, to a lesser extent in the SWIS, space heating; and • understanding of the diversity of loads across different regions throughout the SWIS. This considers varying weather conditions over different regions and varying economic and demographic conditions over different regions.

3.2 Location of new generation

Western Power provides non-discriminatory access to the SWIS and pricing signals to users of the network are intended to aid in the optimisation of the development of the system, including the location of new generation sources. However, as Western Power may not direct the location for new generation, it must make prudent assumptions regarding possible Transmission pole. generation development scenarios in its network development planning process. Each of these factors will affect Western Power’s ability to accommodate all new generation The 2008 Statement of Opportunities (SOO) proposals in a timely and economically efficient published by the Independent Market Operator manner. Western Power’s planning process (IMO) reported that 1,151 MW of new must manage the high levels of uncertainty generation capacity has committed to connect associated with the timing, size and location into the SWIS during the next three years. The of potential future generation sources. The load forecast published in the 2008 SOO will impact of this uncertainty is increased by the also require that an additional 1,368 MW of new generation capacity be connected to the SWIS time taken to complete major transmission to meet electricity demand growth over the next network augmentation projects, such as the 10 years. construction of 330 kV transmission lines. While the construction phase of a generation project The location for this generation capacity is can take as little as two years, establishing a not certain, however it is anticipated that a new transmission line can take seven to 10 considerable proportion of this capacity will be years from conception to commissioning. located south of the Perth metropolitan area in the region between Pinjarra and Collie. This Western Power develops scenarios from the assumption is based on the availability of fuel generation proposals, taking into consideration resources for coal, gas and renewable plant, the current status of those projects. From these as well as compatible process industries for scenarios, planning analyses can be performed cogeneration plant. to assess the impact of various scenarios on

2009 Transmission and Distribution Annual Planning Report 26

the network enabling Western Power to identify • Secondly, with increased base load power elements of commonality between generation generation, generation elsewhere in the development scenarios and where particular network is displaced. Usually this displaced network developments are beneficial to all generation is located near the Perth generation scenarios. As particular generators metropolitan area and due to its proximity to commit to connecting to the network, additional the load, would normally provide dynamic network reinforcement is likely to be required. reactive power support to stabilise the network during faults. When this generation In developing and considering these scenarios, is displaced, the reactive power support Western Power is not recommending particular normally provided by it needs to be sourced projects, however it does need to ensure that from elsewhere. a minimum amount of network reinforcement has been undertaken to ensure that the network Therefore, significant network augmentations plans are robust and allow potential generation would be required to enable the SWIS to developments to meet forecast load growth. accommodate additional generation in the The following paragraphs outline the main south-west region. All or some of the following scenarios and potential network constraints network reinforcements would be required to arising from potential new generation sources. accommodate the new generation proposed in the south-west region: 3.2.1 Southern Generation Development • construction of 330 kV transmission lines Scenario from the south-west region into the Perth There are a number of large generation metropolitan area; proposals for this area and 468 MW of new • installation of additional reactive power generation is committed to connect in the compensation, in the form of Static Var southern part of the SWIS by 2009/10. The Compensators (SVC), shunt capacitor banks new generation proposals are considered within the metropolitan area and/or series line realistic given the ready access to a range of capacitor banks on the major 330 kV infeeds fuel sources and the recent historical levels to the metropolitan area; of generation development in the area. The • imposition of generation scheduling development of new generation sources in the restrictions; southern areas exposes the network to the • installation of additional 330/132 kV following limitations: transformer capacity in the metropolitan area; • increased requirement for reactive power • construction of additional transmission lines support within the metropolitan area; and within the metropolitan area; and • over loading of 330/132 kV transformers • establishing new terminal stations within the interconnecting the 330 kV bulk transmission metropolitan area. and 132 kV sub transmission networks. Western Power is presently preparing a Additional reactive power support is required for Regulatory Test submission relating to the two reasons: provision of a new 330 kV transmission line • Firstly, the four 330 kV transmission lines between the south-west and Perth to facilitate between the south-west generation sources the connection of new generating capacity in and the Perth metropolitan area are all the region. around 200 km long. Lines of this length can transfer no more than 500 MW of power 3.2.2 Northern generation development each before voltage stability limits begin scenario to constrain their power transfer capacity. To maintain stable and secure network The northern part of the SWIS extending operation at loading levels above 500 MW, from the Perth metropolitan area to Geraldton reactive power support is required. Even with is supplied via a number of long parallel this measure, the risks of system voltage 132 kV transmission lines. The distance collapse are significantly increased. between Northern Terminal and Geraldton is

2009 Transmission and Distribution Annual Planning Report 27

approximately 400 km, which results in a long 3.2.3 Metropolitan generation and weak interconnection restricted to very development scenario limited power transfer capability for this area. The electricity transmission network within the This system operates close to its power transfer Perth metropolitan area is characterised by limits and the area is constrained by thermal, high loads and high fault levels. The fault levels voltage and stability limitations. on the 132 kV network within the metropolitan Due to the limitations of this network there region are nearing design levels and the 132 are currently no new committed generation kV network between the metropolitan power proposals in the northern region, although there stations and terminal stations is loaded to is considerable interest in the development of capacity. New generating sources within the both renewable and fossil fuel energy resources metropolitan area will need to be connected in the area. Substantial reinforcements to the to the 330 kV network to manage fault North Country transmission network will be levels. To facilitate this requirement, it may be required before additional generating capacity necessary to establish new 330 kV transmission can be connected in this region. To increase the interconnectors within the Perth metropolitan power transfer capability of the network to the area to connect new power stations with the north of Perth, Western Power has proposed a bulk transmission network. major network augmentation to establish a 330 kV transmission line interconnection between The development of additional generation within Perth and Geraldton. This proposal has passed the Perth metropolitan area will expose the the Regulatory Test as determined by the following network limitations: Economic Regulation Authority (ERA). • higher fault levels; • increased loading of the 330 kV transmission In addition to the network limitations within network within the metropolitan area (for the northern area, the connection of additional some connection locations); generation sources in this area may expose the network within the Perth metropolitan region to • increased loading of 330/132 kV the following limitations: transformers interconnecting the 330 kV bulk transmission and 132 kV transmission • increased requirement for reactive power networks; and support; • increased loading of parts of the 132 kV sub • over loading of 330/132 kV transformers interconnecting the 330 kV bulk transmission transmission network. and 132 kV sub transmission networks; and The retirement of some generators within the • overloading of the 132 kV transmission lines. Perth metropolitan area also exposes some network limitations. These are as follows: Therefore, some additional network augmentation may be required to enable the • reduced reactive power support for the connection of additional generation sources in network during faults; and the area north of Perth. This may include: • increased demand for reactive power • installation of additional reactive power support if metropolitan generation is replaced compensation, in the form of Static Var with remote generation. Compensators (SVC), shunt capacitor banks Therefore the connection of additional within the metropolitan area and/or series line generation sources within the Perth metropolitan capacitor banks on the major 132 kV infeeds area would require some network augmentation, to the metropolitan area; but may also have some beneficial effect • installation of additional 330/132 kV on the network by providing reactive power transformer capacity in the metropolitan area; support. The exact siting of generation within and the metropolitan areas would significantly • establishing new 132 kV transmission lines affect the network development required. The within the metropolitan area. concentration of new generation in the southern

2009 Transmission and Distribution Annual Planning Report 28

part of Perth, alongside existing generation, Merredin into the metropolitan area should would increase network loading and fault levels, any generation connect in this area. Further, requiring some reinforcement. The siting of new significant line losses may result from power generation in the northern part of Perth would transfer across such a weak network. Network initially require the establishment of a new reinforcement costs to cater for the connection 330 kV connector and reinforcements to of significant amounts of generation in this the 132kV transmission network, but should area are likely to be high due to the absence of minimise any fault uprate or reactive power existing 330 kV transmission infrastructure or support requirements. strong points of connection at lower voltages.

Generation at Kalgoorlie 3.2.4 Eastern generation development scenario Kalgoorlie is located approximately 550 km east of the Perth metropolitan area and is connected Recently there has been some interest in to the SWIS via a radial 220 kV transmission generation connections in the Kalgoorlie and line. The 220 kV interconnection from Muja in Merredin area. The following discussion seeks the south-west to Kalgoorlie is 650 km long to provide a general overview of the existing and was originally designed and constructed network and the constraints that are likely to be in 1984 to supply loads in the Kalgoorlie encountered with the connection of generation area. Due to its length, the transmission line in this part of the network. incorporates a complex reactive compensation Generation in the Northam area scheme to adequately control voltages. The line and reactive support system were originally This part of the SWIS is connected to the designed to enable generators to be connected metropolitan area by long and weak 132 kV for emergency stand-by purposes only, to and 66 kV transmission lines. The transmission supply some load when the radial 220 kV line system was originally designed to supply was out-of-service. relatively small loads. There would be significant thermal, voltage and stability constraints In the last 15 years or so, generators have associated with power transfer from Northam/ connected in the Kalgoorlie area to supply local

Kalgoorlie Post and Telegraph Office. Photo Tourism Western Australia.

2009 Transmission and Distribution Annual Planning Report 29

load. Due to synchronous instability problems associated with the operation of this generation, a remedial action scheme (RAS) was installed at Kalgoorlie to island this generation for local and remote faults in the SWIS when power transfer exceeds certain thresholds.

The system was not designed to cater for large abrupt changes in power transfer that result from operation of the RAS (there are limitations in the dynamic range of the reactive power compensation equipment). Therefore while the RAS enhances the transfer capability of the existing system, it also imposes limits on the amount of power that can be exported from generators in the Kalgoorlie area without undertaking additional reinforcements.

Detailed studies would need to be completed to determine whether additional generation plant could be connected in the Kalgoorlie region. The design of the power plant would need to be managed very carefully to ensure that the system operates in a synchronously stable state.

If the amount of generation connected in the Kalgoorlie area exceeds the local load, then power would be transferred from across the 220 kV transmission line into the SWIS via Muja. This has similar effects as the southern generation development scenario with similar network reinforcement requirements.

2009 Transmission and Distribution Annual Planning Report 30

2009 Transmission and Distribution Annual Planning Report 31

4 Description of load areas

The SWIS is grouped into a bulk transmission network and 13 load areas primarily along geographical lines. These load areas are Northern Terminal, Muja, Kwinana, Cannington, Bunbury, Western Terminal, East Perth, Southern Terminal, South Fremantle, East Country, Eastern Goldfields, North Country and Guildford.

The bulk transmission network interconnects rapid load growth due to residential housing these load areas as shown in Figure 3, a developments, whereas growth in the Eastern simplified single line representation of the SWIS. Goldfields area is highly sensitive to the activities of mining companies in response to world metal Historically, these load areas tended to consist prices. As might be expected, the greatest of a number of zone substations centred on a distinctions are between load areas that cover major terminal station. However, with increasing urban and rural areas. numbers of substations being cut into interconnecting transmission lines to minimise The maximum demand forecasts for each load substation establishment costs, the network is area are shown as a percentage of the total becoming increasingly meshed. load for 2009 and 2014 in Figure 4 and Figure 5 respectively. These graphs do not show the Each load area has its own unique affect of private customer loads. characteristics and load growth in the area tends to be influenced by them. For example, The annual peak demand growth for each load the load areas supplying the northern and area, averaged over the period from 2009-2014 southern coastal areas are experiencing is shown in Figure 6.

Load area Immediate network constraints

Bulk transmission Largely driven by generation location decisions

Northern Terminal Thermal capacity of transmission lines and substation capacity shortfalls

Muja Voltage constraints on long lines and distribution network limitations

Kwinana Thermal and voltage constraints on transmission lines and substation capacity shortfalls

Cannington Substation capacity shortfalls

Bunbury Thermal and voltage constraints on transmission lines and substation capacity shortfalls

Western Terminal Substation capacity shortfalls

East Perth & CBD Substation capacity and distribution feeder circuit shortfalls

Southern Terminal Substation capacity shortfalls

South Fremantle Thermal capacity of transmission lines and substation capacity shortfalls

East Country Voltage constraints on transmission lines and substation capacity shortfalls

Eastern Goldfields Voltage and stability constraints on transmission lines – No further generation is possible in this region without detailed system studies

North Country Highly sensitive to connection of generation and/or loads – No further generation is possible in this region without transmission reinforcements

Guildford Terminal Thermal line constraints and substation capacity shortfalls

2009 Transmission and Distribution Annual Planning Report 32

Figure 3: Simplified SWIS single line diagram.

2009 Transmission and Distribution Annual Planning Report 33

Figure 4: Peak demand proportions in 2009.

Current peak demand proportions by load area in 2009

Muja 4% s s North Country 4% Kwinana 8% s

Guildford 5% s s Northern Terminal 24% Eastern Goldfields 4% s

East Perth & CBD 10% s

s South Fremantle 7% East Country 3% s

Cannington 9% s s Southern Terminal 11%

Bunbury 6% s s Western Terminal 5%

Figure 5: Forecast peak demand proportions in 2014.

Forecast peak demand proportions by load area in 2014

Muja 9% • • North Country 5% Kwinana 9% •

Guildford 5% • • Northern Terminal 22%

Eastern Goldfields 3% •

East Perth 9% •

• South Fremantle 6% East Country 3% •

Cannington 8% • • Southern Terminal 10%

Bunbury 7% • • Western Terminal 4%

Figure 6: Forecast annual load growth by load area, averaged over from 2009-2014.

Bunbury

Cannington

East Country

East Perth & CBD

Eastern Goldfields

Guildford

Kwinana

Load Area Muja

North Country

Northern Terminal

South Fremantle

Southern Terminal

Western Terminal

0 1 2 3 4 5 6 7 8 Load Growth (%)

2009 Transmission and Distribution Annual Planning Report 34

2009 Transmission and Distribution Annual Planning Report 35

5 Projects (approved, committed or commissioned)

This chapter provides information of the approved projects, the Regulatory Test submissions, network development projects and the future outlook for each of the 13 load areas within Western Power’s South-West Interconnected System.

The following sections use the terminology considering alternative options including defined below: demand side management and generation • An approved project is defined where solutions. Interested parties are encouraged Western Power’s Board has approved or is to make written submissions in respect to these proposals. In particular, parties should deemed very likely to approve a submitted submit alternative proposals that will alleviate business case for its proposed scope of the network constraints as detailed in this works. Please note that although these are section. considered approved projects, they may still change in timing, scope and cost prior • Network development projects are defined to commencement as a result of revised as projects that have not yet been submitted forecasts and other factors. for approval and do not require a Regulatory • A Regulatory Test submission is required for Test submission. These projects provide an transmission projects with an estimated cost indication of Western Power’s plans for each exceeding $30 million and for distribution load area. Detailed technical and economic assessments of multiple options are carried projects with an estimated cost exceeding out before committing to the particular $10 million, or if the combined transmission project, however, only the preferred option at and distribution components of a project the time of publication is presented here. exceeds $30 million. These projects are reviewed by the ERA to ensure the network The future outlook section provides a more reinforcement proposed by Western Power general picture of the possible long term maximises the net benefit to the state after development of each load area given the current

Rural distribution feeder under construction

2009 Transmission and Distribution Annual Planning Report 36

load forecasts. This section discusses the medium and long term are also provided. Note constraints that are likely to emerge within the that these diagrams are simplified single line next 20 years and the options that could be diagrams and do not depict true geographical used to alleviate them. Projects in this section location. The symbols used for the diagram are are still likely to be in the conception phase shown in Figure 7. and may not contain specific details regarding Please also note that this section does not scope, timing and implementation. include information on the connection of new Diagrams of each individual load area and generators or private customer loads as this how they are expected to develop both in the may be commercially sensitive.

Figure 7: Symbols used in the load diagrams.

Legend

Existing 330 kV Infrastructure Existing 330 kV Line

Existing 220 kV Infrastructure Existing 220 kV Line

Existing 132 kV Infrastructure Existing 132 kV Line

Existing 66 kV Infrastructure Existing 66 kV Line

Existing 33 kV Infrastructure Existing 33 kV Line

Future 330 kV Infrastructure Future 330 kV Line

Future 220 kV Infrastructure Future 220 kV Line

Future 132 kV Infrastructure Future 132 kV Line

Future 33 kV Infrastructure Future 33 kV Line

Normally Open Point Transmission Line Tee Point

2009 Transmission and Distribution Annual Planning Report 37

5.1 Bulk transmission are as important as load forecasts given that the timing, size, and location of new Power is transferred over the 330 and 132 generation connections significantly affect the kV bulk transmission network from five major network development. Consequently, network power stations and a number of smaller performance studies have been conducted interconnected stations to 12 bulk supply assuming that required additional generation terminals for transformation to lower voltages. is connected to the bulk transmission Electrical energy is then distributed to zone network. However, potential generation siting substations supplying localised areas via the is constantly changing, so the information sub transmission network operating at 132 and presented here represents only a snapshot in 66 kV voltages. time. The bulk transmission network comprises the 330 kV network and major 132 kV links Figure 8 shows the bulk transmission load between power and terminal stations. At present area including terminal stations and 330 kV there are four major 330 kV transmission ties transmission lines as of Q4 2008: linking the south-west power stations with the The following projects in the bulk transmission Perth metropolitan area, two major 330/132 network were completed in 2008: kV terminal stations at Northern Terminal and Southern Terminal and three main 330 kV • reactive compensation in the southern load transmission lines within the Perth metropolitan area; area. There are also a number of major 132 kV • convert Southern Terminal to Kwinana line to transmission ties that are considered to be part operate at 330 kV; of the bulk transmission network. • install third 330/132 kV transformer to In assessing the adequacy of the bulk Southern Terminal; and transmission network, generation forecasts • construct Pinjar to Wanneroo 132 kV line.

Figure 8: The bulk transmission network – 2008.

Northern Terminal

Guildford Terminal Southern Terminal Kwinana Kwinana Power Station Kenwick Link

Oakley

Alcoa Pinjarra

Landwehr Bluewaters Terminal Shotts Power Station Kemerton Power Collie Power Station Station Kemerton Muja Terminal

2009 Transmission and Distribution Annual Planning Report 38

5.1.1 Approved projects – bulk The installation of a single 490 MVA, 330/132 transmission kV transformer at Kwinana will benefit the transformer capacity, voltage stability and Neerabup – establish new 330/132 kV voltage recovery time of the system, and reduce terminal station the risk of transformer thermal overload at A new 320 MW generator will connect to the Southern Terminal. 330 kV network at Kwinana and a new 200 MW Please note that a delay in the decommissioning generator will connect to the 330 kV network of the Kwinana Stage B and Stage A generators near Collie in 2008. These new generators will may alter the preferred connection location for increase the power flow through the 330/132 kV this transformer. transformers within the Perth region, such that during an outage of one of the two Northern This project is scheduled to be completed by Terminal 330/132 kV transformers, the other Q4 2009. transformer may be overloaded. Construct Pinjar to Geraldton 330 kV To cater for connection of the new generation double circuit line and to prevent transformer overloading or load shedding, a new 330/132 kV 490 MVA The transmission network in the North Country transformer will be installed at a terminal station load area was designed to supply relatively small in Neerabup. loads distributed over a large geographical area. The network is approaching power transfer The new terminal station will supply substations limits due to thermal, voltage and synchronous at Yanchep, Wanneroo, Clarkson and stability constraints. Joondalup, offloading the transformers at Northern Terminal and the 132 kV transmission The load forecast shows the supply capacity lines supplying the Northern Terminal load area. will be exceeded by peak demand in the The new terminal will also provide substantial summer 2010/11. In addition, the North loss savings for the network. Country transmission network is not capable of supporting the connection of new industrial The Neerabup terminal is optimally located to customers. Reinforcement of the transmission supply the areas of rapid load growth at the network is required to remove these constraints. northern edge of the Perth metropolitan area. Twelve options were considered including the This project is scheduled to be completed by proposed solution of a 330 kV double circuit Q2 2009. transmission line from Pinjar to Geraldton. A Regulatory Test was submitted in late 2007 Kwinana Terminal – install 330/132 kV and the ERA subsequently determined that the transformer proposed reinforcement met the requirements Increased loading of the 330/132 kV bulk of the Regulatory Test. transmission transformers is the prime driver for The proposed reinforcement included: this project. The connection of new generation to the 330 kV network together with the • construction of a new Pinjar-Moonyoonooka retirement of generating plant connected to 330 kV double circuit line; the Kwinana 132 kV busbar increases power • establishment of a new 330/132 kV terminal flow through the Southern Terminal 330 kV substation at Moonyoonooka; transformers into Southern Terminal, South Fremantle and Kwinana load areas. With this • installation of line circuits at Neerabup increased power flow, by summer 2009/10 an Terminal; and outage of one of the existing transformers may • associated distribution work. result in loss of network voltage stability, and by summer 2012/13 an overload of the other transformers in the area.

2009 Transmission and Distribution Annual Planning Report 39

Originally this project has been scheduled for To provide adequate reliability for the entire completion according to the following stages. network the following options are being • Stage 1 - 330 kV line from Neerabup to considered: Eneabba by summer Q4 2010; and 1. Establish South East Terminal (near • Stage 2 - 330 kV line from Eneabba to Oldbury) and a new 330 kV double circuit Moonyoonooka by summer Q4 2011. transmission line between Landwehr Terminal (near Wagerup) and South East Terminal. It should be noted that due to the recent 2. Establish South East Terminal and cut into downturn in the world economy there is a the Shotts to Southern Terminal/Oakley 330 risk that some of the prospective loads or kV transmission line into Landwehr Terminal. generation projects driving this project could (A new double circuit transmission line will be be deferred. There is possibility that this required from Landwehr Terminal to South project might also be deferred in the present East Terminal two years later). environment. 3. Establish South East Terminal and install 5.1.2 Regulatory Test submissions – bulk additional high voltage capacitor banks at transmission South East Terminal and Guildford Terminal. (A new double circuit transmission line will be South-west reinforcement required from Landwehr Terminal to South East Terminal two years later). Forecasts indicate that the bulk transmission network from the Collie region to Perth will 4. Install a Static Var Compensator (SVC) at require additional reactive power by Q4 2011. Northern Terminal (to defer option two, a Power transfer on each of the existing lines will new double circuit transmission line will be result in reactive power losses large enough required from Landwehr Terminal to South to cause a network deficiency. To allow the East Terminal five years later). installation of significant amounts of new 5. Install series compensation in the generation in the south-west region, a network 330 kV bulk transmission lines between augmentation is unavoidable. south‑west generation sources and the

Figure 9: Pinjar to Geraldton 330 kV transmission line.

Geraldton Moonyoonooka

WWF Mungarra Golden Grove Stage 1: New 330 kV terminal and double circuit line Three Springs (initially at 132 kV and 330 kV) Eneabba

Substation EMD Moora 132 kV existing

Cataby Muchea 330 kV new double circuit

Stage 2: Rebuild the existing PJR-RGN-CTB-ENB 132 kV line with 330 kV double circuit Pinjar Neerabup

2009 Transmission and Distribution Annual Planning Report 40

Perth metropolitan area. (A new double circuit 330 kV transmission line from Wells circuit transmission line will be required from Terminal, connecting to existing transmission Landwehr Terminal to South East Terminal lines in the Hacketts Gully area and establish five years later). South East Terminal. 6. Install conductor on the spare circuit of the 9. Establish a 500 kV transmission link to the 330 kV transmission line between Shotts metropolitan area. Terminal (near Collie) and Wells Terminal Western Power has performed system analysis (near Boddington) and rebuild an existing on all the options considered and concluded transmission line to a a new double circuit that option eight - Establish a 330 kV double 330 kV transmission line between Wells circuit transmission line from Collie to Hacketts Terminal and a proposed new Eastern Gully plus South East Terminal - maximises Terminal. the net benefit after considering all alternative 7. Install an SVC at Northern Terminal (a new options. This assessment has been reviewed double circuit 330 kV transmission line from by two independent consultants looking at the Wells Terminal to Hacketts Gully and to technical and economic benefits of each option. establish South East Terminal will be required The consultants concluded that option eight is two years later). the best technical and economical solution. 8. Install conductor on the spare circuit of the Western Power anticipates that a regulatory 330 kV transmission line between Shotts submission will be presented in Q1 2009 and Terminal and Wells Terminal and rebuild an the project is scheduled to be completed by Q4 existing transmission line to a new double 2011.

5.1.3 Future development projects – bulk transmission

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date Reliability following single Install high speed single Transmission Q4 2011 phase to earth faults on phase auto reclosers the 330 kV network (HSSPAR) on all 330 kV transmission lines

2009 Transmission and Distribution Annual Planning Report 41

Figure 10: The bulk transmission network Q4 2013.

Moonyoonooka Terminal

Eneabba Terminal Northern Terminal

Neerabup Terminal Station

Guildford Terminal Southern Terminal Kwinana Kwinana Power Station Kenwick Link South East Terminal Oakley

Alcoa Pinjarra

Landwehr Bluewaters Wells Terminal Terminal Shotts Power Station Collie Power Kemerton Power Station Kemerton Muja Terminal

5.1.4 Future outlook – bulk transmission projects from 2014 onwards include:

The 2008 Statement of Opportunities published • construct a new transmission line to cut by the Independent Market Operator forecast Landwehr Terminal into existing Shotts - that the total system demand would grow Oakley/Southern Terminal 330 kV line; from the 2007/08 peak load by an average of • install third 330/132 kV transformer at around 237 MW per year for the next 10 years Northern Terminal; assuming a 10% probability of exceedence for • establish a 330/132 kV switchyard at the expected economic growth scenario. Cannington Terminal; Therefore, to simply supply the forecast load • construct an additional Southern Terminal – growth, an average of 237 MW of additional Guildford Terminal 330 kV line; and generating capacity will be required every year • construct a double circuit 330 kV line from for the next 10 years. Landwehr Terminal to South East Terminal This equates to at least one new 250 MW and connect the Wells Terminal to Hacketts generator every year to maintain capacity. Gully lines to a 330 kV switchyard (note the location of this connection is still to be In order to accommodate load and generation determined and is not reflected in Figure 11). growth while continuing to operate the South-West Interconnected System (SWIS) in Figure 11 shows the future long term outlook accordance with the Transmission Planning for the bulk transmission load area and the Criteria, Western Power will need to implement developments which could occur based on a number of significant bulk transmission current forecasts. system reinforcements. Some of the major

2009 Transmission and Distribution Annual Planning Report 42

Figure 11: Future outlook - bulk transmission.

Moonyoonooka Terminal

Eneabba Terminal Northern Terminal

Neerabup Terminal Station

Guildford Terminal Southern Terminal Kwinana Kwinana Power Station Kenwick Link South East Terminal Oakley

Alcoa Pinjarra

Landwehr Bluewaters Wells Terminal Terminal Shotts Power Station Collie Power Kemerton Power Station Kemerton Muja Terminal

2009 Transmission and Distribution Annual Planning Report 43

5.2 Northern Terminal lines during the next 10 years. In addition, a number of existing substations will need to be The Northern Terminal load area covers the uprated to ensure fault levels are not exceeded. north of the Perth’s metropolitan region, extending from the coast to Osborne Park and Figure 12 shows the forecast load demand Morley in the south, to Yanchep in the north, within the Northern Terminal load area. and West Swan in the east. The load area Figure 13 shows the existing load area and its represents approximately a quarter of the total substations and transmission lines as of Q4 load in Western Power’s SWIS. 2008: The area contains commercial, light industrial, The following projects in the Northern Terminal residential and semi-rural loads. Long term load area were completed in 2008: development plans indicate that heavy industrial load centres may be developed in the area • establish Henley Brook substation; within 20 years. • Padbury substation – install second transformer; The average annual demand growth for this load area is approximately 4%. If realised, • Morley substation – install third transformer; the forecast load growth would require the and establishment of at least 10 new substations • Yokine substation – install third transformer. and the construction of two new transmission

Figure 12: Northern Terminal five year load growth.

1400

1200

1000

800

600 MW & MVA

400

200

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 44

Figure 13: Northern Terminal load area 2008.

To Regans To Eneabba To Cataby

Kerr McGee Muchea Muchea Local Yanchep To Moora Pinjar Muchea Clarkson Edgewater Wanneroo Henley Brook Malaga To Muja Wanneroo Mullaloo To Kwinana To Northam Padbury Northern To Guildford Terminal Terminal Station

Northbeach Arkana Beechboro

Mt Lawley Morley

To Western Manning St Osborne Park Yokine Hadfields Terminal To James St To East Perth Terminal

5.2.1 Approved projects – Northern The new substation will consist of a single Terminal 33 MVA transformer, with a second transformer installed by 2012 and a third transformer by Padbury substation – install third 2017. transformer The distribution works for the future Joondalup The northern suburbs of Perth have substation will initially consist of four new experienced recent strong growth placing an underground feeders designed to offload increased demand on electricity infrastructure Wanneroo and Mullaloo substations. in the area. Due to the magnitude of load that needs to be transferred from North Beach and The first stage of this project, including the Mullaloo substations, a third transformer will be installation of one transformer and associated required. distribution works will be completed by Q4 2009. The project is scheduled to be completed by Q1 2009. Wangara – establish new substation

Joondalup – establish new substation Landsdale substation is forecast to reach design capacity by Q4 2010 with any excess load to be A new substation in Joondalup will be required transferred to a new Wangara substation. to provide additional capacity to offload Mullaloo and Wanneroo substations. The site for this The substation will initially consist of a single substation is located adjacent to Joondalup city 33 MVA transformer with capability for future centre and this substation is proposed to supply expansion. A second transformer is planned a mixture of commercial, light industrial and to be installed in 2013 and a third transformer residential load in the immediate vicinity. The in 2017. The new substation will be cut into substation will require a 132 kV line cut in along the existing Mullaloo to Landsdale 132 kV line. the existing Mullaloo to Wanneroo 132 kV line. The distribution works for the new substation

2009 Transmission and Distribution Annual Planning Report 45

Figure 14: Joondalup and Wangara substation connection.

To Pinjar To Eneabba Terminal

Yanchep Neerabup Edgewater Clarkson To Muchea

To Northern Wanneroo Terminal Joondalup Mullaloo Wangara Landsdale will initially consist of two underground feeders 5.2.2 Regulatory Test submissions – designed to offload Lansdale substation. Northern Terminal

This transmission and distribution works for Construct Neerabup to Wangara 132 kV line the initial establishment of the substation is Load in the northern suburbs of Perth is rapidly scheduled to be completed by Q4 2010. increasing with existing transmission lines unable Malaga substation – install third to provide capacity during single and double transformer contingencies.

A number of new block load developments To provide adequate reliability for new customers in the Malaga area are expected to push the in the load area the following options are being substation to its capacity by Q4 2010. As the considered: adjacent substations in the area are all forecast 1. Construct a new 132 kV WNO-HKG-WGA to be heavily loaded, the preferred alternative cable. is to expand the capacity of Malaga Substation using a third transformer. 2. Rebuild the transmission lines and install a transformer at Northern Terminal. The project is scheduled for completion by Q4 2010. 3. Construct a new 132 kV cable from Neerabup to Northern Terminal and install a Construct Northern Terminal to Hadfields transformer at Northern Terminal. 132 kV line 4. Construct a new double circuit 330 kV line Increased load growth in the Northern Terminal from Neerabup to Northern Terminal and load area has resulted in heavy loadings on the install a transformer at Northern Terminal. existing 132 kV transmission lines. These lines are unable to provide sufficient supply capacity 5. Construct a new 132 kV cable from following single line outages. The construction of Neerabup to Wangara substation. a new transmission line from Northern Terminal 6. Construct a new 132 kV cable from to Hadfields is proposed to help alleviate Neerabup to Landsdale substation. capacity constraints. 7. Construct a new 132 kV WNO-HKG-WGA The project is scheduled for completion by Q4 2010. line and cable. 8. Construct a new 132 kV double circuit overhead line from Neerabup to Northern Terminal and install a transformer at Northern Terminal.

2009 Transmission and Distribution Annual Planning Report 46

available options, but detailed studies have not yet been completed.

Western Power anticipates that a regulatory submission will be presented in 2009 and the project is scheduled to be completed by Q4 2011.

Flynn (Mather) Drive – establish new substation

The Wanneroo substation will be unable to provide sufficient capacity to supply future load growth beyond 2012. Transferring load to adjacent sites will only provide a short term solution resulting in unreliable supply, such that it is not economically justified.

To provide adequate reliability for new customers in the load area the following options are being considered: 1. Build a new indoor zone substation at Flynn (Mather) Drive (possibly relocated and Transmission pole entry into substation. renamed to Mather Drive substation). 9. Construct a new 132 kV double circuit 2. Temporary transfer of load to adjacent overhead line from Neerabup to Wangara substations. substation. 3. Demand side management. 10. Construct a new 132 kV double circuit 4. Local generation. overhead line from Neerabup to Landsdale 5. Load shedding. substation. Studies to determine the best economic option 11. Demand side management. are currently being assessed. Western Power presently believes that a new substation at Flynn 12. Local generation. (Mather) Drive will maximise the net benefit 13. Load shedding. after considering all available options. However, detailed option analysis has not yet been Studies to determine the best economic option completed. are currently being assessed. Western Power presently believes that a new transmission line Western Power anticipates that a regulatory from Neerabup to Wangara passing through the submission will be presented in Q1 2009 and future Hocking substation site (option nine) will the project is scheduled to be completed by Q4 maximise the net benefit after considering all 2012.

2009 Transmission and Distribution Annual Planning Report 47

5.2.3 Future development projects – Northern Terminal

Constraint Recommended Transmission Forecast Reinforcement / Distribution

Feeders at Hadfields Install one new feeder, and Distribution Q4 2010 substation are heavily replace Hadfield’s H502 and loaded beyond planning limit H504 feeder exit cable. Also upgrade weak and under- rated conductors

Feeders in Morley substation Install two new feeders Distribution Q4 2010 are highly loaded and above and upgrade under-rated/ planning limit weak conductors at Morley substation

Load growth exceeding Install second transformer at Combined Q4 2010 capacity at Henley Brook Henley Brook substation substation

Undervoltage constraint Create interconnection Distribution Q4 2010 at extremities on Muchea between MUC511 and MUC511 feeder RGN508

Feeder loading above Install one new feeder at Distribution Q4 2011 planning limit at Beechboro Beechboro substation substation, and uneven transformer load balance at the substation

Load growth exceeding Install second transformer at Combined Q4 2011 capacity at Joondalup Joondalup substation substation

Scheduled load transfers Install two new feeders at Distribution Q4 2011 from Beechboro substation Henley Brook substation to Henley Brook substation will overload some distribution feeders

Scheduled load transfers Install two new feeders at Distribution Q4 2011 from Mullaloo substation to Joondalup substation Joondalup substation will overload some distribution feeders

Insufficient distribution Install one new feeder at Distribution Q4 2012 capacity to feed Capricorn Yanchep substation to Village load supply Capricorn Village

Load growth exceeding Install second transformer at Combined Q4 2012 capacity at Joondanna Joondanna substation substation

Load growth exceeding Install second transformer at Combined Q4 2012 capacity at Wangara Wangara substation substation

2009 Transmission and Distribution Annual Planning Report 48

Figure 15: Northern Terminal load area - Q4 2013.

To Eneabba To Emu To Regans To Cataby Kerr McGee Muchea Terminal Downs Muchea Local Yanchep Pinjar To Moora Flynn Drive Muchea Neerabup Clarkson Edgewater Henley Brook Malaga To Eastern Terminal Wanneroo Joondalup Mullaloo Wangara Landsdale To Northam Padbury To Guildford Terminal To Hazelmere Warwick Northern Terminal Arkana To Guildford Terminal

Northbeach Beechboro

Joondanna Mt Lawley Morley

Manning St Osborne Park Yokine Hadfields To Western To James St Terminal To East Perth Terminal

5.2.4 Future outlook – Northern Terminal • Northern Terminal – Arkana (NT-A82);

Northern Terminal is a heavily loaded area Possible substation siting includes: and is expected to continue its rapid load • Karrinyup; growth. Major future residential and commercial • Truganina Rd; developments in the area include: • Bayswater; • West Swan and Caversham; • Hocking. • Flynn – Mather Drive industrial estate; • Scarborough highrise building; and While the scope and timing for reinforcements • Area along the north–west coastal line is fairly well defined, external drivers such as (Alkimos, Yanchep, Two Rocks). distribution network limitations, location and rate of development and connection of new To meet the forecast growth in electricity generation sources to the network will influence demand beyond 2020, significant system the actual timing for projects. reinforcement will need to be undertaken. Reinforcements that have been identified Figure 16 shows the future longterm outlook include establishing new substations, up-rating for the Northern Terminal load area and the existing substations, establishing a new terminal developments which could occur based on station, establishing a new transmission line and current forecasts. up-rating existing transmission lines.

The list of proposed future transmission lines include: • Yanchep – Two Rocks (YP-TRS81 & 82); • Pinjar – Two Rocks (PJR-TRS81); • Neerabup – Wangara (NBT-WGA82);

2009 Transmission and Distribution Annual Planning Report 49

Figure 16: Northern Terminal load area – future outlook.

Two Rocks To Eneabba To Emu To Regans To Cataby Kerr McGee Muchea Terminal Downs Muchea Local Yanchep Town Pinjar Yanchep To Moora Flynn Drive Muchea Neerabup Clarkson Edgewater Henley Brook Hocking To South East Malaga Terminal/Wells Terminal Wanneroo Joondalup Mullaloo Wangara Landsdale To Northam Padbury To Guildford Terminal To Hazelmere Warwick Northern Terminal Arkana To Guildford Terminal Truganina Northbeach Stirling Rd Beechboro

Bayswater Joondanna Mt Lawley

Manning St Osborne Park Yokine Morley Hadfields To Western To James St Terminal To East Perth Terminal

2009 Transmission and Distribution Annual Planning Report 50

2009 Transmission and Distribution Annual Planning Report 51

5.3 Muja loads supply their peak load during the summer period. The Muja load area supplies predominantly agricultural loads, with some mining, milling and Local load growth is generally slow, although light industrial loads. It extends from Muja Power there are some developing areas in addition to station to Manjimup and Beenup in the south- recently connected mining loads. Albany, the west, Albany in the south-east, Boddington in main population centre in this region, has had the north and Narrogin in the north-east. Due the most significant load growth and is forecast to the large geographical area, the load area’s to double over the next 10 years. There is also substations supply their peak loads at different significant potential for growth from a new iron times. Substations supplying predominantly ore development in the region. domestic loads normally supply their peak load during the winter period whereas the Figure 17 shows the forecast load demand substations supplying mining and agricultural within the Muja load area.

Figure 17: Muja forecast five year load demand.

250

200

150

MW & MVA 100

50

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2009 Transmission and Distribution Annual Planning Report 52

Figure 18 shows the existing load area and its substations and transmission lines as of Q4 2008:

Figure 18: Muja load area Q4 2008.

To Guildford Terminal To Northern Terminal To Kondinin Landwehr Terminal To Southern Terminal Narrogin South To Kemerton Wagerup Boddington To Southern Terminal Western Collieries Narrogin To Picton To Oakley Worsley

To Kemerton Shotts Wagin

Kojonup Collie Power Station Muja Terminal Katanning

Mount Barker

Bridgetown

Beenup Collie Albany Manjimup

The following projects in the Muja load area The project is schedule for completion by Q4 were completed in 2008: 2009.

• Mount Barker substation – install second Albany substation - installation of 22 kV transformer; capacitor banks on distribution feeders • Kojonup substation - uprating the 132/66 kV transformer; This project will install 22 kV capacitor banks on Albany substation’s distribution feeders. • Katanning substation – Ravensthorpe The project will install five 1 MVAr pole-top standby transformer for emergency capacitors and is required to ensure voltage generation; and levels at Albany remain within the required • Albany substation – Denmark feeder. planning limits.

5.3.1 Approved projects – Muja The project is schedule for completion by Q4 2009. Katanning substation - installation of 22 kV capacitor banks on distribution feeders 5.3.2 Regulatory Test submissions – Muja

This project will install 22 kV capacitor banks Construct Kojonup to Albany 132 kV line on Katanning substation’s distribution feeders. The reinforcement is required to ensure voltage Forecasts for the Lower Great Southern Region levels at Katanning remain within the required indicate that load in the area will almost double planning limits for outages on the 66 KV within the next five years. This will require network supplying the substation. significant reinforcement of supply with the

2009 Transmission and Distribution Annual Planning Report 53

possibility of a new 132 kV transmission line 5.3.4 Future outlook - Muja from Kojonup to Albany and a 220/132 kV The main concern with the Muja load area transformer at Kojonup. relates to the degree of confidence in a number To improve supply capacity in the Lower Great of key industrial developments. Due to the Southern Region the following options will be magnitude of these projects (greater than considered: 100 MVA), the decision on whether they go 1. Carry out transmission line reinforcement ahead will have a large impact on the long term from Kojonup to Albany. planning and development of the Muja load 2. Upgrade existing transmission lines. area. 3. Establish local generation. The major uncertainties that influence the scope 4. Execute demand side management. for strengthening the supply in the Muja load 5. Combinations of the above. area are listed below: • Development of Southdown iron-ore mine Studies to determine the best economic and associated power demand. Grange option are currently being performed by an Resources has stated that it would make its independent consultant. Western Power decision by mid 2009. Without Southdown presently believes that construction of a Kojonup to Albany 132 kV line will maximise the mine, the total load in Muja load area net benefit after considering all available options. within the next 20 years would drop from However, this will need to be confirmed by the approximately 550 MVA to around 450 MVA. independent consultant. Timing for this project will be firmed when customer connection application and Western Power anticipates that the independent contracts are formalised. consultant will present a regulatory submission in Q2 2009 and the project is scheduled to be • The speed of development of Mirambeena completed by Q4 2011. Industrial Estate and associated load growth — in the most recent forecast Mirambeena 5.3.3 Future development projects – Muja load increases by approximately one

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Capacity in the Pingelly/ Install new feeder sections Distribution Q3 2010 Walpole area is limited by and voltage regulator on the voltage drop Brookton feeder

Capacity at Walpole is limited Install second 22 kV feeder Distribution Q3 2012 by voltage drop section from Denmark to Walpole

Capacity at Bremer Bay and Install new feeders from new Combined Q2 2013 Ravensthorpe is limited by Welstead substation voltage drop

2009 Transmission and Distribution Annual Planning Report 54

Figure 19: Muja load area Q4 2013.

Landwehr Terminal To Northern To Kondinin Terminal Wells Terminal To Southern Alcoa Boddington Terminal Narrogin South Wagerup Boddington To Alcoa Pinjarra Western Collieries Ltd Narrogin To Picton

Worsley Bluewaters To Kemerton Power Shotts Station Wagin To Oakley/ Southern Terminal Kojonup Muja Katanning Collie Power Station Terminal

Mount Barker Bridgetown Southdown

Beenup Collie Albany Manjimup

third of the combined Albany and Mount This will result in the construction of the following Barker load. However, this development is lines: suspended indefinitely due to the current • Double circuit 132 kV line between Kojonup economical environment. and Albany; • Strengthening of transmission links between • Single circuit 132 kV line between Muja and Muja and Kojonup — if Southdown mine Kojonup. goes ahead and Mirambeena load growth If Southdown mine and Mirambeena is as forecasted, then at least a single developments go ahead, it will be necessary circuit 220 kV transmission line between to build an additional single circuit 220 kV line Muja and Kojonup will need to be built. between Kojonup and Southdown. In addition, However, because of the ever-increasing the Muja to Kojonup line will need to be upsized difficulty of finding new line routes, it might be to 220 kV. desirable to build that line in a double circuit configuration. The second side of this line Sinclair Knight Merz (SKM) evaluation of options would be reserved for future growth. indicates that staged local generation like diesel peak load lopping units is the most attractive In order to alleviate the shortfall in transmission alternative. This alternative may defer the above capacity to Albany and to identify a preferred mentioned reinforcements by approximately solution, it is necessary to pinpoint the best five years. By this time, the proposed industrial network reinforcement options. developments in the area will become much clearer, and in turn, the network planning will be The current load forecast for the Muja load area based on a more accurate load forecast. predicts that the maximum power demand in the area within the next 20 years will be Figure 20 shows the future long-term outlook for between 450 MVA and 550 MVA. the Muja load area and the developments which could occur based on current forecasts.

2009 Transmission and Distribution Annual Planning Report 55

Figure 20: Future outlook - Muja.

Landwehr To Northern Terminal Terminal To West To Kondinin Kalgoorlie Wells Terminal Alcoa Boddington To Southern Terminal Terminal Narrogin South Wagerup Boddington To Alcoa Pinjarra Western Collieries Narrogin To Picton

Worsley Bluewaters To Kemerton Power Shotts Station Wagin To Oakley/ Southern Terminal Kojonup Terminal Muja Katanning Collie Power Station Terminal

Mount Barker Borden Bridgetown Mirambeena Southdown

Beennup Collie Albany Manjimup

2009 Transmission and Distribution Annual Planning Report 56

2009 Transmission and Distribution Annual Planning Report 57

5.4 Kwinana Both of these major infrastructure projects will bring the convenience and mobility of rapid The Kwinana load area lies along the coastal transit systems to the south-west metropolitan strip bound by Anketell Road in the north, and area. It is expected that these projects will spreads to Mandurah and Harvey Estuary to continue to encourage development in the the south. It roughly follows the administrative area, with residential load growth expected to boundaries of the Town of Kwinana, the Cities of remain strong. The Rockingham and Mandurah Rockingham and Mandurah. All the substations regions in particular are expected to experience in this area supply their peak load during large growth. Industrial load is also expected summer. to increase significantly in the long term, The load area has experienced rapid load as proposals for the establishment of large growth within the past three years as a result industrial parks are realised in the future. of residential, commercial and industrial Overall load growth is expected to increase at developments. Two infrastructure developments an average of approximately 6% over the next are anticipated to have a major long term five years, however some substations within the impact on the area. These are: area are experiencing growth rates as high as • The completion of the South West 10%. Metropolitan Railway project that extends the South West Metropolitan Railway to Figure 21 shows the forecast load demand Rockingham and Mandurah; and within the Kwinana load area. • The extension of the Kwinana freeway to Figure 22 shows the existing load area and its Safety Bay and a further section between the substations and transmission lines as of Q4 Mandurah bypass and Lake Clifton. 2008.

Figure 21: Kwinana forecast five year load demand.

400

350

300

250

200

MW & MVA 150

100

50

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 58

Figure 22: Kwinana load area Q4 2008.

To Bibra Lake To South Fremantle Tiwest Pigment HIsmelt Terminal Plant Broken Hill Alcoa Kwinana Kwinana Kerr McGee BP Kwinana

Kwinana Terminal Kwinana Power Partnership Mason To Southern Terminal Road BP Refinery

Kwinana CSBP Desalination To Cockburn Cement Plant Mandurah To Pinjarra Western Mining Medina Meadow Springs Australian Fused Metals To Pinjarra/Cannington Terminal

Rockingham Parklands

The following projects were completed in the region as well as to transfer load away from Kwinana area in 2008: Mandurah zone substation. The new feeder will • Establish Waikiki substation; predominately offload the MH521 L213 Pinjarra Rd feeder. • Mason Rd substation – install second transformer. This project is scheduled to be completed by Q2 2009. 5.4.1 Approved projects – Kwinana New Waterside Dr feeder from Mandurah New Safety Bay Rd feeder from Waikiki zone substation zone substation The existing MH502 Elizabeth Street feeder A new feeder is being installed to supply the is heavily loaded and experienced up to 377 load growth occurring in the Baldivis region Amps during the 2007 summer period. including developments in the upcoming town A new feeder is required to offload the MH502 centre as well as residential subdivisions. Elizabeth St feeder. Additionally, a number of Additionally, this feeder can help support some existing Mandurah feeders will be reconfigured of the adjacent feeders from Rockingham and to offload highly loaded feeders. Medina prior to a new zone substation being established. This project is scheduled to be completed by Q4 2009. This project is scheduled to be completed by Q2 2009. Waikiki substation – install second transformer New Royston Way feeder from Meadow Springs zone substation Waikiki substation was established to help support the rapid growth currently being A new feeder is being installed to supply experienced in the Rockingham region. This the load growth around the Nambeelup growth is expected to continue and Waikiki

2009 Transmission and Distribution Annual Planning Report 59

Mandurah foreshore. Photo Tourism Western Australia. substation is expected to exceed its thermal Medina substation – install third capacity by 2010. A second transformer is to transformer be installed at Waikiki to increase supply and Numerous residential developments coupled help alleviate capacity constraints in the region. with Kwinana’s natural load growth are forecast This project includes the construction of a single to increase load demand at Medina substation. underground distribution feeder to connect the The substation is expected to approach load to the new Waikiki transformer. capacity by Q4 2010, at which time a third This project is scheduled to be completed by transformer and indoor switchboard is to be Q4 2009. installed at Medina.

Meadow Springs substation – install This project is scheduled to be completed by second transformer Q4 2010.

Meadow Springs substation currently acts 5.4.2 Regulatory Test submissions – as support for the Mandurah substation. The Kwinana capacity at Meadow Springs is forecast to be exceeded by Q4 2009, at which time a second There are no Regulatory Test submissions transformer and indoor switchboard will be expected for the Kwinana load area within the required. This project includes construction next five years. of a single underground distribution feeder to connect customer load to the second transformer.

This project is scheduled to be completed by Q4 2009.

2009 Transmission and Distribution Annual Planning Report 60

5.4.3 Future development projects – Kwinana

Constraint Recommended Transmission Forecast Reinforcement / Distribution Energisation Date

Capacity on existing Waikiki New feeder ‘Currie St’ from Distribution Q4 2009 feeder and Rockingham Waikiki zone substation transformers

Capacity on Rockingham New feeder ‘Tropicana Way’ Distribution Q4 2009 transformers from Waikiki zone substation

Insufficient substation Establish Baldivis substation Combined Q4 2010 capacity

Thermal overload on MSR- Construct a double circuit Transmission Q4 2010 WM 81 and KW-CC/MED 81 line and reconfiguration of lines under N-1 conditions existing lines to create MED- MSR 81 and KW-RO 81.

Insufficient substation Establish East Rockingham Transmission Q4 2011 capacity substation

Insufficient substation Establish Clifton substation Transmission Q4 2012 capacity

Insufficient substation Install third transformer at Transmission Q4 2012 capacity at Mason Road Mason Road

Ageing assets at BP Conversion of BP substation Transmission substation to 132 kV

To cater load growth at Install second transformer at Transmission Q4 2012 Rockingham substation Baldivis

Capacity on Downer South Reinforcement of Downer Distribution Q4 2012 feeder from Mandurah South feeder from Mandurah substation substation

Future load growth in the Upgrade of O/H conductors Distribution Q4 2012 East Rockingham region and on Swinstone St feeder to supply increasing load at shopping centre

Future load growth in the New feeder to supply to Distribution Q4 2013 Amarillo and adjacent Amarillo area from Meadow industrial areas Springs substation

Feeder loading above Installation of Macedonia Distribution Q4 2013 planning limit supplying Hope St feeder from Medina Valley area substation

Insufficient feeders to supply Installation of Murdoch Dr Distribution Q4 2013 load growth to the new feeder from Meadow Springs Singleton and Madora Bay substation areas

2009 Transmission and Distribution Annual Planning Report 61

Figure 23: Kwinana load area Q4 2014.

To Bibra Lake To South Fremantle Tiwest Pigment HIsmelt Terminal Plant Broken Hill Alcoa Kwinana Kwinana Kerr McGee BP Kwinana

Kwinana Terminal Kwinana Power Partnership Mason To Southern Terminal Road BP Refinery

Kwinana CSBP Desalination To Cockburn Cement Plant Medina Mandurah To Pinjarra Western Mining

Meadow Springs Australian Fused Metals To Pinjarra/Cannington Terminal Baldivis Rockingham Waikiki Parklands

5.4.4 Future outlook – Kwinana Eventually, there will be a need to establish a 330 kV terminal site and bring the bulk The Kwinana load area will undergo a large transmission supply close to the Kwinana load amount of network development within the centre, offloading the saturated 132 kV network. next 10-15 years. Rapid residential and commercial development in the region between Voltage constraints in the southern part of Rockingham and Mandurah is expected to the load area are expected to become more underpin strong growth rates in the long term. prominent as residential development at the Large scale industrial parks such as the Hope extremities of the network increases. The Valley-Wattleup, Nambeelup and the Latitude 32 installation of additional shunt capacitors with the development will add to the already strong load construction of newly established substations growth. and the installation of additional transformers can help alleviate these constraints. The emerging constraints facing the Kwinana load area in the long term relate to: The strong load growth in the Kwinana area will also result in decreasing substation capacity. At • Thermal constraints on the 132 kV least three substations would be required to be transmission network; established in the area between 2014 and 2025. • Voltage constraints in the south of the load This does not include any customer funded area; and substations which are also expected. • Substation capacity constraints. Major future projects in the Kwinana load area The increasing load in the Kwinana area include: will result in large amounts of power being • Hope Valley Terminal; transferred across the 132 kV network. These • Golden Bay substation; lines will eventually approach their thermal capacity at which point, Western Power will be • East Rockingham substation; unable to reliably supply the load in Kwinana. • Furnisdale substation.

2009 Transmission and Distribution Annual Planning Report 62

Figure 24 shows the future long term outlook for the Kwinana load area and the developments which could occur based on current forecasts.

Figure 24: Future outlook - Kwinana.

To Bibra Lake To South Fremantle Tiwest Pigment HIsmelt Terminal Plant Broken Hill Alcoa Kwinana Kwinana Kerr McGee BP Kwinana

Kwinana Terminal Kwinana Power Partnership Mason To Southern Terminal Road BP Refinery To Cockburn Cement Kwinana Desalination To Shotts Plant Medina To Southern Terminal CSBP Hope Valley To Cannington Terminal Terminal To Pinjarra East Western Mining Rockingham Mandurah Furnisdale Meadow Springs Australian Fused Metals To Pinjarra/Cannington Terminal Baldivis Rockingham Waikiki Golden Bay Parklands

2009 Transmission and Distribution Annual Planning Report 63

5.5 Cannington The following projects in the Cannington load area were completed in 2008: The Cannington load area covers the south- • Rebuild 132 kV transmission lines creating east metropolitan area, bounded by the Swan and Canning Rivers and extending east to Cannington to Belmont 81 and Welshpool to Mundaring. The load area supplies a broad Belmont/Rivervale 81; mix of load types ranging from industrial, • Cannington Terminal - Uprate of 132 kV commercial, residential to semi-rural. switchyard to 40 kA;

Commercial and industrial loads in the area are • Switching circuits for Kwinana to Southern experiencing strong growth and overall load Terminal line. demand is growing at approximately 3%. The residential areas in Cannington load area are 5.5.1 Approved projects – Cannington well established and domestic load growth is Reinforce Cannington 132 kV transmission expected to remain steady. Urban consolidation network and major development projects, many of which will be located along the shores of the Swan In 2009 any outage on the Southern Terminal and Canning Rivers, will be the main drivers for to East Perth and Cannington to Rivervale 132 domestic load growth in the well-developed kV lines will have a significant impact on security residential areas. for the CBD, East Perth and Cannington load areas. These outages will drive power flow into Figure 25 shows the forecast load demand the CBD through the Welshpool to Belmont within the Cannington load area. 132 kV line, exceeding its thermal capacity and Figure 26 shows the existing load area and its increasing the risk of load-shedding or voltage substations and transmission lines as of Q4 collapse on the network. 2008.

Figure 25: Cannington forecast five year load demand.

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2009 Transmission and Distribution Annual Planning Report 64

Figure 26: Cannington load area Q4 2008.

To East Perth/ Belmont Northern Terminal

Kewdale Welshpool Rivervale

To East Perth/ Bentley Southern Terminal Beckenham To Riverton To Southern Terminal Kenwick Link To Southern Terminal Cannington Terminal To Maddington To Mundaring Weir To Pinjarra/Meadow Springs Collier St Tate St

Victoria Park WEB Forge Clarence St Tomlinson St

This project will construct a new 132 kV line The existing Cannington-Belmont 81 line is from Cannington to Belmont and reconfigure due to be in service Q4 2008 and is planned to the existing Welshpool to Belmont and cut-in Kewdale substation creating Cannington Forrestfield to Kalamunda 132 kV lines. Overall, to Kewdale 81 and Belmont to Kewdale 81. approximately 5 km of new 132 kV transmission The location of the new substation is forecast to line will be required to complete this project. support most of Belmont and Welshpool loads for the coming years until further reinforcements This project is scheduled to be completed in Q1 are implemented. 2009. The substation construction has been Kewdale - establish new substation completed and final commissioning will occur in Q1 2009. The establishment of a new Kewdale substation is required to meet the area’s forecast demand Rivervale and Victoria Park substations - for electricity. The area to be supplied by the 6.6 kV to 22 kV conversions future Kewdale substation consists largely of The Rivervale and Victoria Park distribution industrial loads and is currently supplied from networks are fully loaded with no spare capacity Belmont and Welshpool substations. With an for growth. The network cannot be adequately estimated load growth rate of approximately supported due to surrounding networks 4%, it is forecast that demand for electricity operating at a different voltage levels. This will exceed the area’s capacity by 2008/09. distribution project will uprate the distribution Load forecasts have shown that the Welshpool voltage to 22 kV, being consistent with the substation is expected to exceed capacity surrounding network. in 2009 due to load growth in the area. The The main components for this project are the establishment of a new 132/22 kV substation in installation of 2 km of underground cables and Kewdale would relieve the capacity shortfall. The replacement of 58 distribution transformers. substation will contain one 33 MVA transformer with future capacity for a second and third This project is scheduled to be completed by 33 MVA transformer. Q4 2009.

2009 Transmission and Distribution Annual Planning Report 65

Figure 27: Kewdale substation connection.

New 132 kV line tee’d into Belmont Belmont/Rivervale To East Perth/ Northern Terminal

Kewdale Welshpool Rivervale (Established Q1 2009)

Construct new 132 kV line from Cannington to Kewdale (Q1 2009)

Cannington Terminal

Rivervale substation – install third Bentley – install third transformer transformer Bentley substation supports the load from Rivervale zone substation supplies a mixture Collier Street and Clarence Street substations. of residential and commercial load. A number The location of the new substation allows it to of large commercial block loads are scheduled supply Curtin University, the area’s major load. for connection in the next few years. Future The establishment of the substation with two demand beyond the current connection new 132/22 kV transformers was designed to applications cannot be supplied from existing relieve the capacity shortfall until 2014 when capacity at Rivervale substation. further reinforcements will be required.

Detailed studies have shown that the most A third 132/22 kV 33 MVA transformer is found effective and economical long term solution to be the most economically viable option to for Rivervale is to install an additional 132/22 reinforce the network avoiding load shedding. kV 33 MVA transformer and an indoor 22 kV Other options were considered however, most switchboard. will enhance the network temporarily and a new transformer would still be required in the future. This project is scheduled to be completed by Q4 2010. This project is scheduled to be completed by Q4 2013. Kewdale substation – install second transformer Victoria Park – conversion to new 132/22 kV substation The Kewdale load area consists of large industrial loads. Future commercial block Load forecasts have shown that Welshpool loads are expected to connect into Kewdale 132/22 kV substation and Cannington substation. The single transformer at Kewdale 132/66 kV Terminal station are expecting substation will not be able to keep up forecast shortfalls in transformer capacity in the coming demand. years. It is anticipated that the capacity at Welshpool will be exceed by 2014. The A second 132/22 kV 33 MVA transformer conversion of Victoria Park’s 66/6.6 kV to is required to support the load growth and 132/22 kV operating voltages was shown to be demand at Kewdale substation. the most technically viable option. This project is scheduled to be completed by The new Victoria Park substation will be Q4 2010. supplied by two 132/22 kV transformers with

2009 Transmission and Distribution Annual Planning Report 66

the distribution network upgraded from 5.5.2 Regulatory Test submissions – 6.6 kV to 22 kV by 2011. The location of the Cannington new substation allows it to support load growth There are no Regulatory Test submissions from Rivervale and Welshpool. expected for the Cannington load area within The project is scheduled to be completed by Q4 the next five years. 2013.

5.5.3 Future development projects – Cannington

Constraint Recommended Transmission Forecast Reinforcement / Distribution Energisation Date

Thermal overload on Re-conductor the Transmission Q4 2011 Cannington to Kewdale Cannington to Kewdale 132 132 kV line under N-1 kV line with Venus conductor contingency

Increasing fault levels Cannington load area fault Transmission Q4 2011 at Cannington 132 kV uprate switchyard

Thermal overload on Collier network extension/ Distribution Q4 2012 existing feeder from Collier reinforcement substation

Thermal overload on Uprate Cannington to Tate Transmission Q4 2013 Cannington to Tate St 66 kV St line 103 MVA line under N-1 contingency

Insufficient capacity at Installing third transformer at Transmission Q4 2013 Kewdale substation to meet Kewdale, substation load growth

Insufficient bulk supply Establish 330 kV Cannington Transmission Q4 2013 transformer capacity switchyard

2009 Transmission and Distribution Annual Planning Report 67

Figure 28: Cannington load area Q4 2013.

To East Perth/ Belmont Northern Terminal

Kewdale Welshpool Rivervale

To East Perth/ Bentley Southern Terminal Beckenham Victoria Park To Riverton To Southern Terminal Kenwick Link To Southern Terminal Cannington Terminal To Mundaring Weir To Maddington To Munday/Kalamunda To Forrestdale

Collier St

Tate St

WEB Forge Clarence St Tomlinson St

5.5.4 Future outlook – Cannington The ring conversion requires the gradual offloading of the Clarence Street and Collier The Cannington 66 kV ring is expected to be Street substations’ loads to neighbouring converted to 132 kV by the year 2020, to meet substations, like the Bentley substation, and the growing high density housing development the new Victoria Park 132 kV substation. The in the areas along the Swan River front. These establishment of the Wilson and Kensington residential areas in the Clarence Street and substations will allow a more stable conversion Collier Street substations’ load areas have seen of the 66 kV to 132 kV ring, as they provide a tremendous growth rates in the last two years. second feeder from the Cannington Terminal to The following future major developments in the act as a back-up, and provide more capacity City of South Perth, Town of Victoria Park and for the Clarence Street and Collier Street City of Canning are expected to contribute to substations to be offloaded. The Clarence the high growth rates in the next 10-15 years: Street and Collier Street substations are planned • Bentley Technology Park; to be converted from 66 kV to 132 kV at the same time. • Curtin University of Technology - Bentley Campus Expansion; After the conversion of the Victoria Park • Student Housing for Curtin University; substation to 132 kV, the Tomlinson Street • The Peninsula; and and Web Forge Grating substations will either be uprated to 132 kV, or are planned • The Causeway Precinct. to be decommissioned and have their loads The projects that are related to this 132 kV ring reconnected to the Victoria Park distribution conversion include: feeders. • conversion of Victoria Park to new 132/22 kV After the Clarence Street and Collier Street substation; substations are converted to 132 kV, the Tate • establishment of Wilson substation; Street substation will be the remaining 66 kV • establishment of Kensington substation. substation to be converted to 132 kV. This

2009 Transmission and Distribution Annual Planning Report 68

Tate Street substation conversion requires The following substations require conversion the outage of the Cannington to Victoria Park from 66 kV to 132 kV: 81 line. The N-1 condition of the outage of • Clarence Street; the Cannington to Victoria Park 81 line will • Collier Street; cause the Cannington to Kewdale line and the • Tate Street. Belmont to Kewdale line to overload. Therefore, constructing a second 132 kV CT-VPK 82 line Figure 29 shows the future long-term outlook for will prevent the load area from outages or load the Cannington load area and the developments shedding. which could occur based on current forecasts.

Figure 29: Future outlook - Cannington.

To East Perth/ Belmont Northern Terminal

Rivervale Kewdale Welshpool

To East Perth Bentley To Southern Terminal Beckenham Victoria Tomlinson St Park Collier St WEB Forge Wilson Tate St Clarence St Kenwick Link Kensington To Southern Terminal To Mundaring Weir To Maddington To Forrestdale Cannington To Munday/Kalamunda To Riverton Terminal

2009 Transmission and Distribution Annual Planning Report 69

5.6 Bunbury to the area’s main roads, an extension of the Perth-Mandurah railway to Bunbury and other The Bunbury load area covers the south-west infrastructure developments in the region are coastal region that stretches from Pinjarra expected to encourage more people and in the north to Augusta in the south. Major businesses to move to the region. A number industries for the region are tourism, mining and of residential and industrial developments are agriculture. already earmarked for the area over the next The area has experienced high load growth over few years, with major industrial developments the last decade, with the growth concentrated expected in and around Bunbury and in the region’s major metropolitan centers of Kemerton. A major water desalination plant in Bunbury, Busselton and Pinjarra, where the Binningup is also proposed. growth has been underpinned by tourism, To meet the growing demand whilst improving coastal-lifestyle seekers and an increased system security, reliability and quality of supply penetration of air-conditioning. Load growth has for the area, extensive network reinforcements averaged approximately 6% over the last three are planned for the area over the next decade. years. Figure 30 shows the forecast load demand The rapid load growth is expected to continue within the Bunbury load area. over the next five years, with urban growth observers forecasting that Bunbury will be the Figure 31 shows the existing load area and its fastest growing region in Western Australia, if substations and transmission lines as of Q4 not in Australia as a whole. Proposed upgrades 2008.

Figure 30: Bunbury forecast five year load demand.

350

300

250

200

150 MW & MVA

100

50

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 70

Figure 31: Bunbury load area Q4 2008.

To Mandurah To Meadow Springs/ Cannington Terminal To Wagerup/ Pinjarra Southern Terminal Alcoa Coolup Pinjarra To Southern Oakley Terminal

Kemerton To Shotts Power To Shotts To Kwinana To Landwehr Terminal To Muja Kemerton Marriot Rd Terminal To Worsley

Barrack Silicon Smelter Picton To Muja Bunbury Harbour Westralian Capel Sands

Busselton Margaret River

The following projects in the Bunbury load area Coolup substations when required. were completed in 2008: This project is scheduled to be completed by • Busselton substation - Ludlow feeder voltage Q1 2009. regulator; Busselton substation – install new • Bunbury Harbour substation - Robertson transformer Drive feeder; and • Marriott Rd substation - Benger regulator. Work is underway to install a new 33 MVA, 132/22 kV transformer at Busselton substation 5.6.1 Approved projects – Bunbury in order to meet Busselton’s forecast demand for electricity. The load area supplied by Pinjarra substation – install second Busselton substation has experienced high transformer and two new feeder circuits load growth in the past decade. The high load Pinjarra substation is forecast to connect growth is forecast to continue as the area’s more than 15 MVA of new load over the infrastructure, mainly roads, are improved. next five years. As the substation has only one distribution feeder, the ability to connect An additional 5 MVAr of capacitance will also additional load to Pinjarra is limited. be added to Busselton’s network as part of this project in order to provide additional reactive To meet the forecast load growth, a new support to the region. indoor, 22 kV switchboard and second 33 MVA transformer and two new distribution feeders will This project is scheduled to be completed by be installed at Pinjarra substation. The additional Q1 2009. capacity will be used to support Mandurah and

2009 Transmission and Distribution Annual Planning Report 71

Margaret River – upgrade substation and remaining transmission lines resulting in low construct 132 kV transmission line voltages at Busselton and Margaret River.

Margaret River substation is supplied via a To avoid the impacts of low voltages at 37 km radial, mostly overhead, 66 kV line from Busselton and Margaret River, the following Busselton substation. An outage on the 66 kV options are being considered: line would leave Margaret River reliant on less 1. Uprating existing Picton to Busselton than 4 MVA of distribution transfer capacity transmission lines. from Busselton and Beenup substations, 2. Uprating existing Busselton to Margaret River leaving more than 50% of Margaret River’s load transmission lines. unsupplied. The reliability of supply to Margaret 3. Installing additional reactive compensation at River is expected to further decline as load Busselton and Margaret River. grows. 4. Installing a new 132 kV line from Picton to To improve security of the system, a new Busselton. Busselton to Margaret River 132 kV double 5. Installing a new 132 kV line from Beenup circuit line and a new 132/22 kV transformer at substation to Margaret River. Margaret River will be installed. One side of the 6. Demand side management. double circuit line will initially be operated at 66 kV as a replacement of the existing Busselton to 7. Installing local generation in the region. Margaret River 66 kV which will be subsequently Cost benefit analysis of the options being removed. considered, shows that establishing a new This project is scheduled to be completed by 132 kV line from Picton to Busselton by Q4 2009. converting one of the existing 66 kV lines to 132 kV will provide the optimal solution 5.6.2 Regulatory Test submissions – at minimal cost and risk. The new line will Bunbury ensure voltages in the region do not fall below statutory limits and will lay the foundation for the Construct second 132 kV Picton to progressive retirement of the 66 kV network in Busselton line the region.

This project aims to improve system stability A regulatory submission for the Picton to for the Busselton and Margaret River regions. Busselton 132 kV line will be submitted in 2009 Studies show that loss of the Picton to and the project is scheduled to be completed Busselton 132 kV line at peak demand may by Q4 2012. cause excessive voltage drops along the

Figure 32: Establish Picton to Busselton 132 kV line.

Picton

Westralian Sands Establish a Picton to Busselton Capel 132 kV line

Busselton

2009 Transmission and Distribution Annual Planning Report 72

5.6.3 Future development projects – Bunbury

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Thermal overload Uprate Pinjarra to Alcoa Transmission Q4 2010 for a number of N-1 Pinjarra 132 KV line to 244 contingencies when Alcoa MVA Pinjarra’s generator GT1 is at high output

Load growth in parts of Install new feeder along Distribution Q3 2010 Bunbury approaching Sandridge Rd from Bunbury capacity Harbour

Load growth in Busselton Install new 22 kV Distribution Q3 2011 region approaching capacity underground cable sections on East Busselton feeder

Insufficient capacity at Install second 33 MVA Combined Q4 2012 Busselton substation to transformer at Busselton meet forecast load growth substation

Insufficient capacity at Install third transformer at Combined Q4 2013 Marriot Road substation to Marriot Road substation meet forecast load growth

Load growth in Preston Install new 22 kV Distribution Q3 2013 Beach region approaching underground cable from capacity Wagerup substation

2009 Transmission and Distribution Annual Planning Report 73

Figure 33: Bunbury load area Q4 2013.

To Mandurah To Meadow Springs/ Cannington Terminal To Wagerup/ Pinjarra Southern Terminal Alcoa Coolup Pinjarra To Southern Oakley Terminal

Kemerton To Shotts Power To Shotts To Kwinana To Landwehr Terminal To Muja Kemerton Marriot Rd Terminal To Worsley

Barrack Silicon Smelter Picton To Muja Bunbury Harbour Westralian Capel Sands

Busselton Margaret River Margaret River

5.6.4 Future outlook - Bunbury It should be noted that none of the proposed developments listed above have been Bunbury load area is expected to continue confirmed. to experience high load growth. Besides natural load growth, mainly from increased To cater for the forecast high load growth in air-conditioning uptake, the following proposed the area whilst maintaining gazetted quality major developments in Bunbury load area are of supply limits, it is planned to progressively expected to contribute to the high growth rates: convert Bunbury load area’s 66 kV network • Binningup Desalination Plant; to 132 kV, with Margaret River’s 66 kV plant to be the last to be retired. By the year 2020, • Expansion of Water Authority’s pumping Busselton, Capel and Coolup would have been stations such as Ravenswood to support the converted to 132 kV. proposed Binningup Desalination Plant; Major projects to convert some of Bunbury load • Expansion of SIMCOA’s silicon smeltering area’s 66 kV network to 132 kV include: facilities; • Conversion of one of the existing Picton to • Expansion of Crystal Global’s 18 “Millennium Capel-to-Busselton 66 kV lines to 132 kV; Inorganic Chemicals”; • Installation of a second 330/132 kV 490 MVA • Kemerton Industrial Park; and transformer at Kemerton; • Numerous residential developments along • Splitting of existing Kemerton to Marriot the coast from Preston Beach all the way to Road 132 kV line into two separate lines; Augusta. • Establishment of a new substation in Bunbury, preferably in Gelorup;

2009 Transmission and Distribution Annual Planning Report 74

• Conversion of Capel and Coolup zone Figure 34 shows the future long term outlook for substations to 132 kV; and the Bunbury load area and the developments • Extensive reconfiguration of the existing 132 which could occur based on current forecasts. kV in order to increase transmission capacity.

Figure 34: Future outlook - Bunbury.

To Mandurah To Meadow Springs/ Cannington Terminal To Wagerup/ Pinjarra Southern Terminal Alcoa Coolup Pinjarra To Southern Oakley Terminal

Kemerton To Shotts Power To Kwinana To Shotts Kemerton To Landwehr Terminal Terminal To Muja

Marriot Rd To Worsley

Barrack Silicon Smelter Picton To Muja Bunbury Preston Park Harbour Westralian Capel Sands

Busselton Margaret River Margaret River

2009 Transmission and Distribution Annual Planning Report 75

5.7 Western Terminal loads, natural growth and the increased uptake of residential air-conditioning. A number of the The Western Terminal load area supplies the area’s major commercial customers, including area bound by the Perth CBD to the east, the University of Western Australia, Claremont Swan River to the south, the west coast, and Shopping Village, and Sir Charles Gairdner and the suburbs of Scarborough and Yokine to the Hollywood Private hospitals, have indicated they north. Western Terminal supplies predominantly are likely to double demand over the next 10 commercial and residential customers. years.

The western suburbs are generally well The forecast average annual load growth for established. The proposed residential, substations in the Western Terminal load area is commercial, industrial and infrastructure approximately 3% per year. developments in the area indicate that most of the area’s substations are likely to experience Figure 35 shows the forecast load demand steady load growth. within the Western Terminal load area.

Load growth in the area will be driven mainly Figure 36 shows the existing load area and its by the expansion of existing major commercial substations and transmission lines as of Q4 2008.

Figure 35: Western Terminal forecast five year load demand.

250

200

150

MW & MVA 100

50

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 76

Figure 36: Western Terminal load area Q4 2008.

To Northern Terminal Medical Centre University To Cook St

Western Terminal Nedlands Shenton Park

To North Fremantle Cottesloe Herdsman Parade Wembley Downs

To Amherst

5.7.1 Approved projects – Western Cottesloe substation – 6.6 kV to 11 kV Terminal conversion

Cottesloe substation – upgrade existing The Cottesloe distribution network currently substation to 132 kV operates at 6.6 kV and will reach its capacity by 2009. The uprate to 11 kV will create Cottesloe substation will be upgraded to an additional 66% network capacity to 132 kV to increase the substation’s capacity accommodate load growth and new customer in order to meet forecast local demand. The connections in the region. existing substation capacity will be exceeded by Q4 2008. This project will be carried out in two stages. Stage one will prepare the distribution network This project requires the conversion of for conversion to 11 kV. Stage two will convert Cottesloe’s operating voltages from 66/6.6 kV to the network including all switching and 132/11 kV and replacement of the substation’s relocation of feeders to progressively change existing transformers. The substation will contain all the distribution transformer voltage taps to two 33 MVA transformers, with provision for two operate at 11 kV. more transformers in the future. This project is scheduled to be completed by The project has the additional advantage by Q4 2009. avoiding expenditure on maintenance of aged Wembley Downs substation – increase 66 kV plant. Most of Cottesloe’s 66 kV plant is capacity, convert distribution to 11 kV more than 35 years old and would otherwise require extensive maintenance or replacement The transformers at Wembley Downs substation within the next 10 years. will be replaced with 32 MVA transformers and the distribution voltage will be raised from This project is scheduled to be completed by 6.6 kV to 11 kV. This project will increase the Q4 2009. distribution network and substation capacity in order to meet forecast local demand.

2009 Transmission and Distribution Annual Planning Report 77

This project will reuse the transformers Nedlands – establish new substation previously located at North Perth substation. The load growth in the area surrounding The distribution works will be carried out in two Nedlands has necessitated the need to expand stages. Stage one will prepare the distribution Western Power’s electricity infrastructure. network for conversion to 11 kV. Stage two will Nedlands substation currently operates at convert the network including all switching (and 66/6.6 kV with three 15-15.5 MVA transformers. relocation of feeders) to progressively change all the distribution transformer voltage taps to To supply sufficient capacity to meet load operate at 11 kV. growth, the following options are being considered: This transmission and distribution project will be 1. Establish a new 132/11 kV substation; staged with the total works to be completed by 2. Establish a new 66/11 kV substation; Q4 2009. 3. Retain the existing substation and upgrade 5.7.2 Regulatory Test submissions – or reinforce the network as required; Western Terminal 4. Replacement of the existing 66/6.6 kV substation transformers; Medical Centre – establish new substation 5. Demand side management; The expansion of Hollywood Private Hospital 6. Local generation. and load growth in the area surrounding Sir Charles Gairdner Hospital has necessitated the Studies to determine the best economic option need to expand Western Power’s electricity are currently being assessed and the option infrastructure. The medical centre substation analysis has not yet been completed. currently operates at 66/6.6 kV with three 13-15 MVA transformers. Western Power anticipates that a regulatory submission will be presented in 2009 and the To supply sufficient capacity to meet load project is scheduled to be completed by Q4 2012. growth, the following options are being considered: 1. Establish a new 66/11 kV substation; 2. Establish a new 66/6.6 kV substation; 3. Retain the existing substation and upgrade or reinforce the network as required; 4. Replacement of the existing 66/6.6 kV substation transformers; 5. Demand side management; 6. Local generation.

Studies to determine the best economic option are currently being assessed and the option analysis has not yet been completed.

Western Power anticipates that a regulatory submission will be presented in 2009 and the project is scheduled to be completed by University of Western Australia. Photo Tourism Western Q4 2010. Australia.

2009 Transmission and Distribution Annual Planning Report 78

5.7.3 Future development projects – Western Terminal

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Insufficient capacity at Establish 132/11 kV Combined Q4 2013 Shenton Park 66 KV Shenton Park substation fall at Shenton Park

Insufficient capacity at Establish 66/11 kV Combined Q4 2013 University 66 kV substation University

Figure 37: Western Terminal load area Q4 2013.

To Northern Terminal Medical Centre University To Cook St Shenton Park

Western Terminal

Nedlands

To North Fremantle Herdsman Parade Cottesloe Wembley Downs

To Amherst

5.7.4 Future outlook – Western Terminal Some infill developments of higher densities are also expected, which is expected to further Beyond 2013, Western Terminal load area is boost the area’s load growth. expected to continue to experience high load growth. The load growth will be underpinned Also, though not confirmed, the following major by increased uptake of air-conditioning, new customers in the area have indicated that they residential developments and expansion of will be further expanding their facilities: existing commercial facilities. The load area • Sir Charles Gairdner Hospital; supplies the majority of Western Australia’s • The University of Western Australia (UWA); and affluent suburbs and as the area becomes • Claremont Shopping Centre. more and more affluent, air-conditioning uptake is expected to further increase. Even though It should be noted that the quantum and timing the load area is reasonably mature, new of the developments listed above have not been developments are expected in re-zoned areas. confirmed.

2009 Transmission and Distribution Annual Planning Report 79

Based on historical load growth trends and the • Replacement of existing 66/6.6 kV projected developments, it is forecast that more Herdsman Parade substation with a new transmission assets (both lines and substations) 66/11 kV substation; and in the load area will run out of capacity between • Conversion of an existing 66 kV line from 2013 and 2020. To resolve the capacity Western Terminal to Cottesloe substation to shortfalls expected beyond 2013, the following 132 kV. projects are proposed in the Western Terminal load area: Figure 38 shows the future long term outlook for the Western Terminal load area and the • Replacement of existing 66/6.6 kV Shenton developments which could occur based on Park substation with a new 132/11 kV current forecasts. substation; • Replacement of existing 66/6.6 kV UWA substation (located within UWA) with a new 66/11 kV substation;

Figure 38. Future outlook – Western Terminal.

To Northern Terminal Medical Centre University To Cook St Shenton Park

Western Terminal

Nedlands

Herdsman Parade To North Fremantle Cottesloe Wembley Downs

To Amherst

2009 Transmission and Distribution Annual Planning Report 80

2009 Transmission and Distribution Annual Planning Report 81

5.8 East Perth & CBD projects within the East Perth area include the Perth Arena, Raine Square and Bishop’s See The East Perth and CBD load area includes the developments. Perth Central Business District (CBD), Town of Vincent, City of Subiaco, and parts of Maylands. Demand in the region has the potential to The load area is made up of commercial increase rapidly within the next 10 years. ‘The Link’ project (previously known as Northbridge and residential customers, with loadings Link), Landcorp’s foreshore re-development and concentrated in the densely populated areas projects along East Perth all have the potential of West Perth, East Perth and the CBD. The to increase load demand greatly. Although majority of the substations within the load area the timing for these projects has not yet been are supplied from the East Perth Terminal and all confirmed, the load demand in the area will peak during the summer periods. experience much higher growth rates if they are fully realised. The potential for load growth in the area is largely related to the overall growth in the Figure 39 shows the forecast load demand Western Australian economy and the resulting within the East Perth and CBD load area. increase in commercial activity. The majority of Figure 40 shows the existing load area and its the load growth is located in the CBD, West substations and transmission lines as of Q4 Perth and East Perth areas. Overall load growth 2008. has averaged approximately 3% in the last three years; however a large amount of commercial The following projects were completed in the development currently underway within the East Perth and CBD area in 2008: greater CBD region is expected to increase this • James Street to Milligan Street 132 kV cable figure to approximately 5% in 2012. Notable replacement.

Figure 39: East Perth & CBD forecast five year load demand.

600

500

400

300 MW & MVA 200

100

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 82

Figure 40: East Perth & CBD load area Q4 2008.

To Northern Terminal

To Belmont Summers St

To Mt Lawley Joel Tce

North Perth East Perth Terminal

Cook St

James St Wellington St Wellington St Forrest Ave To Western Terminal

Milligan St Hay St To Southern Terminal

5.8.1 Approved projects – East Perth & shortage in the CBD and to accommodate load CBD growth.

Joel Terrace substation – 66 kV to 132 kV This distribution project is scheduled to be conversion completed by Q4 2009.

The Joel Terrace substation will be converted to Hay Street & Forrest Avenue substations – 132 kV operation to increase the substation’s new feeder pairs transmission capacity and meet forecast load. This project proposes two new feeders to The conversion also will replace Western run between Hay Street and Forrest Avenue Power’s ageing 66 kV assets at the site. substations. The new underground feeders This project will install one 60 MVA three will increase capacity in the East Perth area winding transformer and associated 11 kV accommodating future load growth. Additionally, switchboards. A single 132 kV cable will the new feeders will allow reconfiguration of connect Joel Terrace substation to East Perth the existing network to improve backup supply Terminal. The site will initially operate with both capability between Hay Street and Forrest the 132 kV switchyard and the existing 66 kV Avenue. switchyard. This distribution project was originally scheduled This project was planned for completion by to be completed by Q4 2008, however has Q4 2008, although delays in acquiring a new been delayed to Q4 2009. switchboard may delay the project to Q4 2009. Reactive Support in the Metropolitan Area Hay Street & Milligan Street substations – (Cook Street substation) new feeder pairs This project will install additional reactive power This project proposes two new feeders to in the Perth metropolitan area. Four 5 MVAr run between Hay Street and Milligan Street capacitor banks are planned for installation substations. The new underground feeders will at Cook Street substation by Q4 2009. The help to alleviate the distribution transfer capacity additional reactive support is required to

2009 Transmission and Distribution Annual Planning Report 83

address a shortfall in reactive power caused by 5.8.2 Regulatory Test submissions – East increased load in the metropolitan area and the Perth & CBD connection of new generation in the south-west CBD – establish new substation region. These capacitor banks will improve the voltage stability of the network and help Load growth in the Perth CBD is expected to compensate the load at Cook Street substation increase over the next few years with multiple and defer the need for the third transformer by large customer connection requests. The CBD one year. substations at Hay Street and Milligan Street have almost reached full distribution capacity This project is scheduled to be completed in Q4 with approved customer connections for Perth 2009. Arena, Century City, City Square and Raine Square exhausting the majority of distribution North Perth substation – install third capacity. transformer The CBD network must maintain compliance Load demand at North Perth substation is with the technical rules, specifically referring to forecast to approach its existing capacity by the CBD. Western Power must ensure that each summer 2010/11. At this time, a third 132/11 CBD feeder is “backed up” with a feeder from kV transformer is planned for installation. This a different substation. This ensures that supply will ensure that there is sufficient capacity to can be maintained even following an entire supply current and future load in the area. The substation outage. However, this requirement third transformer will also minimize the risk of places a significant demand on distribution thermal overload on existing transformers and feeder circuits. ensure increased reliability of supply to North Furthermore, CBD substations must maintain Perth. supply following the loss of two transmission This project is scheduled to be completed in Q4 assets. In the CBD, the loss of two transmission 2010. lines can isolate an entire substation. Although distribution feeders will supply loads, the Uprate Mount Lawley to James Street remaining transmission assets must be 132 kV transmission line adequately rated. Forecasts suggest that the CBD capacity will be exceeded by Q4 2011. The 132 kV cables from James Street to Milligan Street have been replaced to increase To provide adequate supply for new and existing capacity at Milligan Street substation. Following customers the following options are being this upgrade, the substation will be restricted considered: to 114 MVA, based on the Mount Lawley to • Build a new 2 x 60 MVA 132/11 kV James Street 132 kV overhead line rating. This transformer indoor substation at James rating is limited by the protection, SCADA, Street in Northbridge; DES and metering components at both Mount • Build a new 2 x 60 MVA indoor substation at Lawley and Milligan Street substations. This Murray Street in the CBD; project seeks to replace these components to • Build a 330/132 kV terminal and 132/11 kV a minimum rating of 900A increasing the firm substation at James Street; capacity at Milligan Street substation to 132.1 MVA. • Upgrade the Wellington Street substation to 132 kV; The project is scheduled to be completed in Q4 • Demand side management; 2010. • Generation in the CBD; • Uprate the CBD distribution voltage to 22 kV.

Studies to determine the best economic option are currently being assessed. Western Power presently believes a new CBD substation at James Street will maximise the net benefit,

2009 Transmission and Distribution Annual Planning Report 84

Perth. Photo Tourism Western Australia.

however a detailed option analysis has not yet • Upgrade the Forrest Avenue substation to been completed. 132 kV;

Western Power anticipates that a regulatory • Upgrade the Wellington Street substation to submission will be finalised in 2009 and the 132 kV; project is scheduled to be completed by Q4 • Demand side management; 2011. This timing may be considerably delayed • Generation in the CBD. if development in the area does not eventuate. Studies to determine the best economic option Bennett Street – establish new substation are currently being assessed. Tully Road will be significantly cheaper than the Bennett Street Load growth in the East Perth area is expected option, but does present significant difficulty in to increase with the potential for significant land future cable connection. Detailed option analysis redevelopment. The ageing Forrest Avenue has not yet been completed. substation supplies power to a large portion of the area, but will be unable to continue reliable Western Power anticipates that a regulatory supply when the load increases beyond submission will be finalised in 2009 and the 39.5 MVA. The Forrest Avenue substation site project is scheduled to be completed by Q4 is too small too consider a third transformer and 2013. This timing may be considerably delayed cannot easily be expanded. if development in the area does not eventuate.

To maintain supply and provide capacity for future growth, Western Power is considering the following options for reinforcement: • Build a new 2 x 60 MVA indoor substation at Bennett Street in East Perth; • Build a new 2 x 60 MVA substation at Tully Road in East Perth;

2009 Transmission and Distribution Annual Planning Report 85

5.8.3 Future development projects – East Perth & CBD

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date Double contingency outage Re-conductor East Perth Transmission Q4 2010 of East Perth to Southern to Belmont 132 kV line with Terminal dual line, causes Venus conductor strung at overload on East Perth to 100°C Belmont 132 kV line Distribution transfer capacity One new West Perth Distribution Q4 2010 shortage in West Perth area feeder from Cook Street substation Feeder capacity approaching New Mt Lawley feeder from Distribution Q2 2010 planning limit in Mt Lawley area North Perth substation Feeder capacity approaching New Leederville feeder and Distribution Q4 2011 planning limit in Leederville cable upgrade from North area Perth substation Feeder capacity approaching New Mt Hawthorn feeder Distribution Q4 2011 planning limit in Mt Hawthorn from North Perth substation area Feeder capacity approaching New Maylands feeder from Distribution Q4 2012 planning limit in Maylands area Joel Terrace substation Feeder capacity approaching New Subiaco feeder from Distribution Q4 2013 planning limit in Subiaco area Cook Street substation

Figure 41: East Perth load area Q4 2013.

To Northern Terminal

To Belmont Summers St Joel Tce To Mt Lawley Joel Tce

North Perth East Perth Terminal

Cook St

James St/CBD Wellington St Wellington St To Western Terminal

Milligan St Bennett St Hay St To Southern To Bentley Terminal

2009 Transmission and Distribution Annual Planning Report 86

5.8.4 Future outlook – East Perth & CBD the load demand required from these projects. It is estimated that at least three substations The East Perth and CBD network is likely to face would be required in the future, two of which are two emerging constraints in the next 20 years as currently being looked at by Western Power. demand for power increases: • Decreasing substation capacity; and The increasing load also means that the existing 132 kV transmission lines supplying the East • Saturation of the 132 kV transmission lines. Perth and CBD load areas will eventually There have been a number of highly publicised saturate in the future. At this point, Western development projects proposed for the CBD and Power will be unable to reliably supply the load East Perth foreshore within the next 20 years. in East Perth and CBD in a safe and efficient Some of these include: manner. Eventually, there would be a need to • The Link Project (EPRA); either extend the East Perth 132 kV switchyard so that new 132 kV transmission lines/cables • East Perth Power Station redevelopment could be built, or establish a 330 kV terminal site (EPRA); and bring the bulk transmission supply directly • Riverside project (EPRA); and into the CBD. Both of these options would help • Perth Waterfront Project (Landcorp). decrease loadings on the 132 kV transmission lines and ensure that any future development is All of these projects indicate a strong desire not constrained by Western Power’s electricity for development of the existing East Perth and network. CBD areas. It is expected that load growth will increase strongly in the next 10-15 years as Figure 42 shows the future long term outlook these projects (and more) become an increasing for the East Perth and CBD load area and the reality. As it stands, Western Power’s current developments which could occur based on electricity infrastructure would be unable to meet current forecasts.

Figure 42: Future outlook - East Perth & CBD.

To Northern Terminal

To Belmont Summers St Joel Tce To Mt Lawley

North Perth East Perth Terminal Cook St To Western Terminal James St/CBD Terminal To Northern Terminal Wellington St Wellington St

Milligan St Bennett St Hay St To Southern To Bentley CBD Substation Terminal

2009 Transmission and Distribution Annual Planning Report 87

5.9 Southern Terminal The main constraints facing the Southern Terminal load area during the next 10 years relate The Southern Terminal load area supplies a to shortfalls in substation capacity. The forecast region from Riverton and Canning Vale in the load growth will require five new substations to north, to Cockburn Cement in the west and be established in the area over the next 10 years. Byford in the south. Substations in this area supply a mixture of commercial, industrial Figure 43 shows the forecast load demand within and residential customers, with the peak load the Southern Terminal load area. occurring during the summer period. Figure 44 shows the existing load area and its Many substations in the area have experienced substations and transmission lines as of Q4 rapid load growth over the last five years due 2008. to increased land development activities. The forecast average growth rate for substations in The following projects in the Southern Terminal the Southern Terminal load area within the next load area were completed in 2008: five years is approximately 6% per year. • Byford substation – install second transformer.

Figure 43: Southern Terminal forecast five year load demand.

700

600

500

400

300 MW & MVA

200

100

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 88

Figure 44: Southern Terminal load area Q4 2008.

To Bentley To East Perth Terminal

Murdoch Riverton To Cannington Terminal

Southern Terminal To Kenwick Link To Guildford To Wagerup/Alcoa Pinjarra To South Fremantle To Shotts/Oakley Terminal Canning To Cannington Terminal Vale Gosnells

Glen Iris Southern River To Kwinana To Landwehr Terminal To Kwinana Cockburn Cement Byford To Kwinana/Medina

Cockburn Cement Ltd

5.9.1 Approved projects – Southern shopping centres in Armadale. As a result, Terminal additional network capacity will be required. This project encompasses the installation of a Southern River substation – cut into new feeder from Byford substation to Armadale Southern Terminal to Wagerup 132 kV line CBD area and reinforcement of Butcher Road, This project requires reinforcement at Southern Highway North, L309 South West Highway River substation. The Southern Terminal feeders. to Wagerup 132 kV line runs alongside the This distribution project is scheduled to be Southern River substation. This line will be cut completed by Q1 2009. into the substation via a new 1.3 km double circuit overhead line. This reinforcement will Byford substation – reinforcement of provide the substation with an alternate supply, Alexander Road feeder and installation of thereby reducing load on the existing 132 kV voltage regulator on L4085 Sunrays Street line from Southern Terminal to Cannington feeder Terminal. This will ensure sufficient capacity is maintained until other planned reinforcements The load of Alexander Road feeders is expected can be implemented. to increase in the next few years due to new residential developments in the area. It has been This project is scheduled to be completed by identified that the presence of fault under-rated Q1 2009. conductors on the feeder has caused reliability Byford substation – installation of new problems. These conductors are located on the feeder to Armadale CBD and network feeder’s backbone and would impact almost all reinforcement of the customers connected onto the feeder.

The load on the Butcher Road and Highway Extensive feeder length and small-sized North feeders has increased substantially in conductors have resulted in customers on recent years due to new residential subdivision George Road feeder experiencing poor quality developments in and expansion of two major of supply. The feeder has a sparse network and

2009 Transmission and Distribution Annual Planning Report 89

serves a large number of semi-rural customers. conductor, which has limited the discrimination The installation of a new voltage regulator between protection devices and adversely is expected to improve supply quality of the affects reliability. The proposed upgrade aims to feeder. remove these limitations.

This distribution project is scheduled to be This first part of this project is scheduled to completed by Q4 2009. be completed by Q4 2008 with the remaining portion to be completed by Q2 2010. Murdoch – install second transformer Gosnells substation – reinforcement of This project involves the installation of a Crandon North, Walter Roadd West and second 33 MVA 132/22 kV transformer at Corfield Road North feeders (reinforcement Murdoch substation, which is expected to of Gosnells feeder in preparation of exceed its capacity by Q4 2009. A capacity commissioning of the Maddington shortfall at Riverton substation necessitated substation) a load transfer from Riverton to the Murdoch The presence of the new Maddington substation in 2007. Two additional load substation will increase fault levels in the area. transfers are expected to occur in 2009 and This project involves the reinforcement of fault 2011. These load transfers in addition to under-rated and undersized conductors on numerous block loads at Fiona Stanley Hospital, Crandon North, Walter Road West and Corfield Murdoch University and Jandakot Airport will Road North feeders. The reinforcement works increase load demand at Murdoch substation will allow load transfers between Gosnells and significantly. To meet the increased load Maddington substations. demand a second transformer is required to be installed. This distribution project is scheduled to be completed by Q3 2010. This project is scheduled to be completed by Q4 2009. Willetton – establish new substation

Gosnells substation – install Ferres Drive Load growth at Canning Vale substation feeder has continued to increase rapidly. Despite a recent load transfer to the new Southern River The load on 85 Wheatley Street feeder is substation, the substation is forecast to reach steadily increasing having peaked beyond its its full design capacity by Q4 2010. Significant maximum design capacity during Q1 2007. new block loads and land developments around Jandakot Airport will also occur in the coming A new feeder from Gosnells substation will be years. A new substation is needed to support installed to supply the Darling Range area. As a this power demand. result, the 85 Wheatley Street feeder can then be used to supply new developments in the The proposed Willetton substation will be Kelmscott area. situated on a Western Power owned site along Modal Crescent. This project will require the This distribution project is scheduled to be establishment of a new substation with one completed by Q4 2009. 33 MVA transformer and line works to cut into Riverton feeder upgrades – distribution the Southern Terminal to Canning Vale 132 kV works line. Four new underground and overhead feeders The RTN502 Cypress Road and RTN515 Webb from the proposed substation will connect in to Street feeders have been overloaded due to the existing network. They will be used to supply weakness at the start of these two feeders. existing and future industrial loads and provide Additionally, these two feeders are located next back up supply during network disturbances. to each other, making load transfers virtually impossible within this part of the network. There This project is scheduled to be completed by are also various sections of under fault rated Q4 2010.

2009 Transmission and Distribution Annual Planning Report 90

Maddington – establish new substation Cockburn Cement conductor upgrades – distribution works Load growth at Gosnells substation has continued to increase rapidly despite recent There are a number of identified under-rated load transfers to the new Southern River conductors located within the Cockburn substation. The substation is forecast to reach Cement distribution network. The fault currents its full design capacity by summer Q4 2010. from Cockburn Cement zone substation are To prevent capacity shortage at Gosnells already high and are further increased by substation a new substation is to be built at connecting PPGs on some feeders. These Maddington. The Western Power owned site upgrades are required to ensure the safety of in Maddington is close to the areas of high the public as well as improve the reliability of the load growth and adjacent to an existing 132 network. kV transmission line. This project will establish This project is scheduled to be completed by a single 33 MVA transformer and line works to Q4 2010. cut into the Cannington to Gosnells 132 kV line. Load forecasts have indicated that adjacent 5.9.2 Regulatory Test submissions – existing substations will not have the capacity Southern Terminal to offload Gosnells substation. The project will include significant distribution works connecting There are no Regulatory Test submissions four new underground and overhead distribution expected for the Southern Terminal load area feeders. within the next five years.

This project is scheduled to be completed by Q4 2010.

Gosnells town centre at night. Photo courtesy City of Gosnells.

2009 Transmission and Distribution Annual Planning Report 91

5.9.3 Future development projects – Southern Terminal

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Loading limits exceeded on Reinforce Alexander RMU Distribution Q4 2010 Butcher Road feeder feeder to offload Butcher Road feeder

Insufficient distribution Install new feeder from Distribution Q3 2011 capacity on L545 Southern Southern River substation River Road and L11 Ranford Road feeders to supply new green field subdivision in Southern River and Forrestdale areas

Undersized and fault Replace undersized and Distribution Q4 2011 under-rated conductors on under-rated conductors on Terence Street, Wheatley Terence Street, Wheatley Street and Walter West Street and Walter West feeders feeders

Under-voltage at end of Feeder upgrades to CC507 Distribution Q4 2011 CC507 Hammond Road Hammond Road feeder. feeder

Insufficient distribution Install new feeder at Distribution Q4 2011 capacity on Chamberlain Southern River substation Street and L22 Ranford Road feeders from Southern River substation

Load growth at Southern Install a third transformer at Combined Q4 2012 River substation exceeds Southern River substation capacity

Load growth at Willetton Install a second Willetton Combined Q4 2012 substation exceeds capacity substation transformer

Load growth at Cockburn Establish a new substation Combined Q4 2013 Cement substation exceeds in Forrestdale area capacity

2009 Transmission and Distribution Annual Planning Report 92

Figure 45: Southern Terminal load area Q4 2013.

To Bentley To East Perth Terminal

Murdoch Riverton To Cannington Terminal

Southern Terminal To Kenwick Link To Guildford To Cannington Terminal To South Fremantle To Shotts/Oakley Terminal To Cannington Terminal Willetton Maddington

Gosnells Canning Vale Glen Iris Southern River To Kwinana To Alcoa Pinjarra/ Wagerup To Landwehr Terminal To Kwinana Forrestdale Cockburn Cement Byford To Cannington Terminal To Kwinana/Medina

Cockburn Cement Ltd To Pinjarra/Meadow Springs

5.9.4 Future outlook – Southern Terminal Increase demand will also come from the new Fiona Stanley Hospital, redeveloped Jandakot By the year 2020, there will be a number of new Airport commercial area, new Murdoch zone substations established in the Southern University campus and Australian Marine Terminal load area to meet the forecast load Complex in Henderson. The proposed Hope growth and new block loads. Valley and Wattleup Redevelopment Project New residential developments will continue which includes approximately 900 Ha of land to fill in the vacant areas to the south of the zoned for industrial use will require further suburbs of Canning Vale and Gosnells towards transmission reinforcements. Southern River and Armadale, and in the New zone substations that could be required suburbs of Byford and Brookdale. There is in the Southern Terminal load area from 2014 also a high degree of potential development onwards include Armadale, Henderson, activity in the areas within the Cockburn Cement Jandakot and Rossmoyne. substation boundary, especially in the suburbs of Spearwood, Atwell, Success, Beeliar, Figure 46 shows the future long term outlook Yangebup, Munster and Coogee. for the Southern Terminal load area and the developments which could occur based on current forecasts.

2009 Transmission and Distribution Annual Planning Report 93

Figure 46: Future outlook - Southern Terminal.

To Bentley To East Perth Terminal

Rossmoyne Murdoch Riverton To Cannington Terminal

Southern Terminal To Kenwick Link To Guildford To Cannington Terminal To South Fremantle To Shotts/Oakley Terminal To Cannington Terminal Willetton Maddington Jandakot Gosnells Canning Vale Glen Iris Southern River To Kwinana To Alcoa Pinjarra/ Wagerup To Landwehr Terminal Armadale To Kwinana Forrestdale Cockburn Cement Byford To Cannington Terminal To Kwinana/Medina

Cockburn Cement Ltd To Pinjarra/Meadow Henderson Springs

2009 Transmission and Distribution Annual Planning Report 94

2009 Transmission and Distribution Annual Planning Report 95

5.10 South Fremantle during the summer period. Most of this area is well established with load growth expected to The South Fremantle load area is relatively remain steady at 3% averaged over the next five compact with the majority of the load demand years. originating from the city centre and the Port Figure 47 shows the forecast load demand of Fremantle. The load area extends south to within the South Fremantle load area. Beeliar, east to the Kwinana Freeway and north to the Swan River. Substations in the area Figure 48 shows the existing load area and its supply a mixture of commercial, industrial and substations and transmission lines as of Q4 residential customers and supply their peak load 2008.

Figure 47: South Fremantle forecast five year load demand.

350

300

250

200

150 MW & MVA

100

50

0 2009 2010 2011 2012 2013

MW MVA Year

Figure 48: South Fremantle load area Q4 2008.

To Cottesloe To Cottesloe

North Fremantle Amherst To Southern Terminal

Edmund St

South Fremantle Terminal

Bibra Lake

To Kwinana O’Connor Myaree Australian Paper Mills

2009 Transmission and Distribution Annual Planning Report 96

Fremantle fishing boat harbour. Photo Tourism Western Australia.

The following project in the South Fremantle load upgrade aims to alleviate these two issues. area was completed in 2008: This project is scheduled to be completed by • Installation of the second transformer at Bibra Q4 2009. Lake substation. Edmund Street stage two feeder upgrades 5.10.1 Approved projects – South Fremantle The load on the E316 South Street feeder has AMT512 Lefroy Road Interconnection been loaded to approximately 320 Amps during the summer period, which is above planning The existing AMT512 Lefroy Road feeder is limits. close to overload and also suffers from under- voltage at the end of the feeder. Reinforcement A new feeder from Edmund Street zone is required to address these two issues. The substation is being installed to supply the South proposed project will create a proper Y-Split Fremantle area and split the E316 South Street configuration as well as improve reliability. feeder into two.

This project is scheduled to be completed by This project is scheduled to be completed by Q1 2009. Q4 2009.

Norma Road North feeder upgrades Amherst and O’Connor feeder upgrades

This feeder has a backbone of 95 sq mm XLPE There are a number of sections of the network cable, which is only rated for 210 Amps. As a supplied from Amherst and O’Connor zone result, the amount of load on this feeder has substations that have reached capacity been constrained to meet planning criteria. limitations. The network in the area is generally fairly strong, except for a number of small Additionally, there is a requirement to balance sections, which this project will target. the load between power transformers at Myaree zone substation. The MYR508 Norma Road This will ensure that there are no overloads North feeder is located on TX2, which is currently and that there is adequate distribution transfer the lightest loaded transformer. The proposed capacity within the network.

2009 Transmission and Distribution Annual Planning Report 97

This project is scheduled to be completed by To provide capacity to supply this area, the Q2 2010. following options are being considered:

O’Connor substation – install third 1. Establish a new substation at Bicton; and transformer construct a 132 kV South Fremantle- O’Connor-Bicton-Amherst Street ring. A new 66/22 kV third transformer will be installed at O’Connor substation due to a capacity 2. Convert O’Connor substation from 66 kV to shortfall by summer 2011. The installation of this 132 kV system. transformer will delay the planned conversion 3. Convert O’Connor and Myaree substation to 132 kV, resulting in significant cost savings. from 66 kV to 132 kV system. Also, the installation of the transformer will allow 4. Load transfers to other substations. load to be transferred from Myaree to O’Connor substation and hence delaying the conversion of 5. Local generation. Myaree substation. 6. Demand side management.

This project is scheduled to be completed by Option analysis is currently being carried out Q4 2010. to determine the most economically viable and technically feasible solution. Western Power 5.10.2 Regulatory Test submissions – South presently believes the conversion of O’Connor Fremantle and Myaree substations to 132 kV substation South Fremantle network reinforcement will provide the most net benefit.

Load growth in the area supplied by the 66 kV Western Power anticipates that a Regulatory substations at O’Connor, Myaree and Australian Test will be submitted in 2009, with project Paper Mill is forecast to exceed substation and completion by Q4 2012. transmission line capacity.

Figure 49: South Fremantle network reinforcement (O’Connor and Myaree 132 kV substation conversion).

South Fremantle Terminal

Stage 1 – Convert O’Connor to 132 kV by Q4 2012

O’Connor Myaree Australian Paper Mills Stage 2 – Convert Myaree to 132 kV by Q4 2013

2009 Transmission and Distribution Annual Planning Report 98

5.10.3 Future development projects – South Fremantle

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Feeders overloading at Edmund Edmund Street Distribution Q4 2009 Street zone substation feeder upgrades

Fault rating exceeded on Replace feeder Distribution Q2 2010 distribution conductors at conductors at Cockburn Cement and Australian Cockburn Cement Paper Mills substations and Australian Paper Mills substations

Existing feeder/s at Australian New feeder from the Distribution Q4 2010 Paper Mills Zone are forecast to Australian Paper Mills become overloaded. Required to zone substation meet upcoming load growth

Under-voltage on nearby Cockburn New feeder from Distribution Q2 2010 Cement Feeders. Also required to Bibra Lake zone transfer load away from Cockburn substation Cement zone substation

Existing feeder at Amherst zone New feeder from Distribution Q2 2011 substation are forecast to become Amherst zone overloaded. Required to meet substation upcoming load growth

A planned and unplanned outage Construct a 132 Transmission Q4 2012 of the South Fremantle to Amherst kV line from South Street 132 kV line and the Northern Fremantle to Amherst Terminal to Western Terminal by reconnecting 132 kV line causes an overload the existing South on the Western Terminal to Cook Fremantle to Edmund Street 132 kV line Street line

Load growth at Myaree substation Convert Myaree Combined Q4 2013 exceeds capacity substation to 132 kV

2009 Transmission and Distribution Annual Planning Report 99

Figure 50: South Fremantle load area Q4 2013.

To Western Terminal To Cottesloe

North Fremantle Amherst To South Terminal

Edmund St

South Fremantle Terminal

Bibra Lake

To Kwinana O’Connor Myaree Australian Paper Mills

5.10.4 Future outlook – South Fremantle The O’Connor-Myaree-Australian Paper Mills 66 kV ring is also noted as an ageing network. The South Fremantle load area is relatively well Therefore, asset replacement is required to established with little development activity. maintain the safety and reliability of electricity However, system studies indicate that there will supply to the South Fremantle load area. be a capacity shortfall in the southern part of Western Power’s proposed project would South Fremantle in the next few years. This is alleviate the need to replace these ageing assets mainly due to the natural load growth as well as as the conversion involves the establishment of the connections of future industrial, commercial new substations. and infrastructure loads. As there is little development in the South In order to solve the capacity shortfall, it is Fremantle load area, current system studies proposed that the O’Connor-Myaree-Australian show that there will be sufficient capacity in the Paper Mills 66 kV ring be reinforced. The current remaining substations of South Fremantle load proposed plan is to convert both O’Connor area for the next 15 years. substation and Myaree substation from 66 kV to 132 kV system using 60 MVA transformers. Figure 51 shows the future long-term outlook Forecast studies show that this proposed for the South Fremantle load area and the option would provide sufficient capacity for the developments which could occur based on southern part of South Fremantle load area for current forecasts. the next 15-17 years.

2009 Transmission and Distribution Annual Planning Report 100

Figure 51: Future outlook – South Fremantle.

To Western Terminal To Cottesloe

North Fremantle Amherst To Southern Terminal

Edmund St

South Fremantle Terminal

Bibra Lake

To Kwinana O’Connor Myaree Australian Paper Mills

2009 Transmission and Distribution Annual Planning Report 101

5.11 East Country demand is expected to average approximately 4% over the next five years and is expected to The East Country load area covers primarily be steady due to sustained mining activity. Wheatbelt areas to the east of the Perth metropolitan area, and is bounded by Sawyers Figure 52 shows the forecast load demand Valley in the west and Southern Cross in the within the East Country load area. east. The network in the East Country load area Figure 53 shows the existing load area and its supplies a mixture of wheatbelt, water pumping, mining, and residential loads. substations and transmission lines as of Q4 2008. Prior to 2007, load growth in this area has been slow with the growth rate less than 1%. The following project in the East Country load In 2007, the load increased substantially due to area was completed in 2008: the mining and resources boom experienced • Reinforcement to allow paralleling of 66 kV in Western Australia. The forecast annual load and 132 kV networks.

Figure 52: East Country forecast five year load demand.

160

140

120

100

80

MW & MVA 60

40

20

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 102

Figure 53: East Country load area Q4 2008.

To West Kalgoorlie Terminal Southern Cross Yilgarn

Yerbillon Merredin Terminal Carrabin

Merredin

Baandee Cunderin Kelleberrin

Northam Terminal

To Northern Terminal Wundowie Sawyers Valley Kondinin Bounty

To Darlington

Mundaring Weir

To Cannington To Narrogin South Terminal Terminal

5.11.1 Approved projects – East Country Construct second 132 kV transmission line from Merredin Terminal – Merredin Sawyers Valley – 132 kV substation substation conversion A single 132 kV transmission line connects Sawyers Valley presently has two 13 MVA Merredin Terminal to Merredin zone substation. transformers. The substation is supplied from For a contingency outage of this line, supply Cannington Terminal and Northam substation. to Baandee, Carrabin, Cunderdin, Kellerberrin, Load forecasts indicate that Sawyers Valley Merredin, and Yerbillon zone substations will substation will be unable to provide sufficient be significantly weakened. To strengthen the capacity during and beyond summer 2010. To network and improve reliability, a second 132 kV provide adequate and reliable power supply for overhead transmission line will be constructed the customers in the East Country load area to provide increased security and reliability. Sawyers Valley will be converted to operate at 132 kV. This project is scheduled to be completed by Q4 2011. The project is scheduled to be completed by Q4 2010. 5.11.2 Regulatory Test submissions – East Country

There are no regulatory test submissions expected for the East Country load area within the next five years.

2009 Transmission and Distribution Annual Planning Report 103

5.11.3 Future development projects – East Country

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Capacity at Hyden is limited Install voltage regulator on Distribution Q1 2009 by voltage drop the Hyden feeder

Capacity at Burracoppin is Install voltage regulator on Distribution Q1 2009 limited by voltage drop the Burracoppin feeder

Capacity at Toodyay is Install voltage regulator on Distribution Q1 2009 limited by voltage drop the Toodyay feeder

Capacity at Beverly is limited Install voltage regulator on Distribution Q1 2010 by voltage drop the York feeder

Load growth exceeds (1) Move SV loads from Transmission Q4 2011 thermal capacity of the 66 kV line to 132 kV Q4 2011 Cannington to Northam 66 line; eventually remove kV line SV from 66 kV line (2) Install 40 M Var 66 kV capacitor bank at NOR to boost Var compensation

Figure 54: East Country load area Q4 2013.

To Western Kalgoorlie Terminal Southern Cross Yilgarn

Yerbillon Merredin Terminal Carrabin

Merredin

Baandee Cunderdin Kelleberrin

Northam Wundowie Kondinin Bounty To North Terminal Sawyers Valley

Mundaring Weir

To Cannington To Darlington To Narrogin South Terminal Terminal

2009 Transmission and Distribution Annual Planning Report 104

5.11.4 Future outlook – East Country bank at Northam substation by 2014 to provide reactive power compensation on the East Country load area has four main 66 kV sub system. weaknesses: • Convert Wudowie to 132 kV operation by 1. Low voltages on the Mundaring Weir, cutting into the Northern Terminal-Northam Sawyers Valley, Wundowie and Northam 66 132 kV line by 2017. kV network, during a fault on the Cannington Terminal-Mundaring Weir 66 kV line; • Rebuild the Cannington Terminal-Mundaring 2. The over-loading and ageing of the Weir-Sawyers Valley-Wundowie-Northam Cannington Terminal-Mundaring Weir- line 66 kV line to 132 kV when the 66 kV Sawyers Valley-Wundowie-Northam 66 kV supply reaches the end of its useful life span. line; However, this rebuilding will be deferred to beyond 2020 because of the above 3. The load on the Merredin Terminal-Merredin approaches. 132 kV transmission line has reached 20 MVA. In addition, should we lose this line, the • Construct a Muchea to Northam 132 kV 66 kV system may collapse; and line to provide supply for the Toodyay 4. Majority of the primary assets, 66 kV and Chidlow areas. This project is to be transformers and 66 kV transmission lines completed by 2030. will be reaching the end of their useful life • Construct two new zone substations in less than 10 years. Furthermore, many including Toodyay, Chidlow to supply these switchyards were designed and constructed two areas. This project is to be completed by as outdoor yards and are also ageing. 2030.

The following solutions should be staged as Figure 55 shows the future long-term outlook the long term strategy for the above network for the East Country load area and the weaknesses: developments which could occur based on • Installation of a 66 kV 40 MVAr capacitor current forecasts.

Figure 55: Future outlook – East Country.

To Western Kalgoorlie Terminal To Muchea Southern Cross Yilgarn

Yerbillon Merredin Terminal Carrabin

Toodyay Merredin

Baandee Cunderdin Kelleberrin

Northam Kondinin Bounty Sawyers Valley Wundowie Mundaring Weir Chidlow

To Northern To Cannington To To Narrogin South Terminal Terminal Darlington Terminal

2009 Transmission and Distribution Annual Planning Report 105

5.12 Eastern Goldfields suddenly may necessitate rapid changes to the network reinforcement plans, and therefore The Eastern Goldfields load area supplies require close monitoring. predominately mining loads in the vicinity of Kalgoorlie. The power station in Muja load area The substations at Narrogin South, Kondinin, provides the major supply to the load area via Merredin and Yilgarn supply areas that are a radial 220 kV line. The 220 kV line from Muja mature and experiencing insignificant growth. reaches Kalgoorlie through part of the East There is some potential for mining, industrial and commercial development in the region to Country load area. accelerate demand at these substations. The electricity demand in the Eastern Goldfields Figure 56 shows the forecast load demand depends heavily on the activities of mining within the Eastern Goldfields load area. industry. The mining activities in turn are largely dependent on international commodity prices. Figure 57 shows the existing load area and its Historically, load growth has varied coinciding substations and transmission lines as of Q4 with the output demand from the mines. 2008.

The load growth predicted for the area is The following project was completed in the approximately 3% per year excluding the Eastern Goldfields load area in 2008: average growth of the mining loads. The mining • Eastern Goldfields – reduction of 132 kV fault loads’ potential to change the growth rate clearance times.

Figure 56: Eastern Goldfields forecast five year load demand.

200

180

160

140

120

100

MW & MVA 80

60

40

20

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 106

Figure 57: Eastern Goldfields load area Q4 2008.

Black Flag Piccadilly

West Kalgoorlie Parkeston Terminal Boulder

Parkeston Parkeston Fimiston Power Station

Western Mining Smelter Western Mining Kambalda Jan

To Yilgarn

5.12.1 Approved projects – Eastern Black Flag substation – install third Goldfields transformer

Piccadilly substation – install third In 2008, the capacity at Black Flag substation transformer was exceeded due to unexpected addition of mining load. Projected natural load growth indicates that Piccadilly substation will exceed capacity by Q4 Black Flag substation is located about 40 km 2008. This substation is located in a high load north of Kalgoorlie Terminal. The only feeder of growth area with a large number of residential other substations close to Black Flag feeders is and commercial developments in Kalgoorlie. Kalgoorlie Terminal 33 kV supply. This will contribute to insufficient supply capacity The most technically and economically feasible and increased risk of power supply interruptions option to the Black Flag supply shortfall is to to customers. install a third transformer. A third transformer was required by November This project requires: 2008 but delayed to November 2009 due to transformer delivery. • installation of a third transformer; • installation of a new 33 kV switchboard; and This project requires: • distribution work as required. • installation of a third transformer; • installation of a new 11 kV switchboard; and This project is scheduled to be completed in Q4 2011. • distribution works for a new underground feeder circuit from Piccadilly substation and Boulder substation – install 33 kV circuit a new feeder cable to split the heavily loaded breaker Lionel West feeder. At Boulder zone substation, one of three This project is scheduled to be completed in Q4 transformers is used as the backup for the 2009. transformers at Boulder and West Kalgoorlie Terminal substations.

2009 Transmission and Distribution Annual Planning Report 107

Currently, due to the absence of a 33 kV requirement. To comply with the requirement, circuit breaker, when paralleling the backup WKT - BKF 132 kV line is required. transformer with one of the two transformers This project may fall under Regulatory Test if at Boulder substation, it is required to blackout steel poles are used. The selection of the poles some customers. will be decided during design stage.

This project is designed to install a new circuit To provide adequate reliability the following breaker, to allow fast and flexible switching options are being considered: action without the attendance of the field 1. Construct a second 132 kV West Kalgoorlie operator when it is required to perform the to Black Flag line; parallel of two transformers as described above. 2. Transfer loads to neighbouring substations; In turn, the reliability and safety of Boulder substation supply will be further improved. 3. Install generation for backup supply to Black Flag substation; and The required in service date of this project is Q4 4. Execute demand side management. 2011. Detailed studies to determine the best economic 5.12.2 Regulatory Test submissions – option are currently being assessed and option Eastern Goldfields analysis has not yet been completed. Western Power anticipates that a new transmission line Construct second West Kalgoorlie to Black will be required. Flag 132 kV line Western Power will attempt to provide a Black Flag substation is fed by a radial 132 kV regulatory submission during early 2009 and line and supplies loads that are well over the project is scheduled to be completed by Q4 20 MW, exceeding Technical Rules 2012.

5.12.3 Future development projects – Eastern Goldfields

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Overloaded cable in Install new 11 kV feeder to Distribution Q3 2009 Piccadilly, Kalgoorlie existing cable

Load growth at Kambalda Install new sections and Distribution Q1 2010 is approaching capacity reconfigure 11 kV feeders

Capacity north of Kalgoorlie Install voltage regulator on Distribution Q2 2010 is limited by voltage drop the 33 kV North Kalgoorlie feeder

Power supply shortfall Increase IPP’s power (local Combined Q4 2009 generation) exports

2009 Transmission and Distribution Annual Planning Report 108

Figure 58: Eastern Goldfields load area Q4 2013.

Black Flag Piccadilly

West Kalgoorlie Parkeston Terminal Boulder

Parkeston Parkeston Fimiston Power Station

Western Mining Smelter Western Mining Kambalda Jan

To Yilgarn

5.12.4 Future outlook – Eastern Goldfields • The 220 kV power supply to Eastern Goldfields is constrained to 130 MW; The Eastern Goldfields region is connected • Supply demand is increasing substantially. to the SWIS via a 650 km long 220 kV radial The current load forecast indicates the load line with reactive support from SVCs based is approaching the system capacity limit; and on saturated rectors at Merredin and West • Operation above the limit will create risk of Kalgoorlie terminals. The 220 kV interconnection synchronous instability and risk of voltage was commissioned in 1984 and was designed collapse. to provide up to 170 MW transfer to West Kalgoorlie Terminals. Eastern Goldfields capacity consists of: • Transmission transfer; The major concern for the load area in the • Local generation. next 20 years is the capacity shortfall due to the transmission limits on the 220 kV The long term strategy to resolve the capacity interconnection. Specifically: shortfall is tabled in the following.

Recommended Reinforcement Transmission / Forecast Distribution Energisation Date

Uprate existing 220 kV Muja to West Kalgoorlie Transmission Q4 2017 line to 275 kV if needed

Construct a new 330 kV line from Muja to West Transmission Q4 2030 Kalgoorlie if needed

2009 Transmission and Distribution Annual Planning Report 109

Finally, the following projects are also envisaged Figure 59 shows the future long-term outlook to accommodate the proposed customer driven for the Eastern Goldfields load area and the industrial park at Coolgardie (Q4 2016) and the developments which could occur based on residential subdivision at Kalgoorlie (Q4 2022). current forecasts. However, these projects are uncertain and their timing is not firm.

Recommended Reinforcement Transmission / Forecast Distribution Energisation Date

Establish new substation in Coolgardie Combined Q4 2016

Establish new substation in North Kalgoorlie Combined Q4 2022

Figure 59: Future outlook – Eastern Goldfields.

Black Flag Piccadilly

North Kalgoorlie

West Kalgoorlie Parkeston Terminal Boulder

Parkeston Parkeston Fimiston Power Station Coolgardie

To Muja Western Mining Smelter Western Mining Kambalda Jan

To Yilgarn

2009 Transmission and Distribution Annual Planning Report 110

2009 Transmission and Distribution Annual Planning Report 111

5.13 North Country resulted in zero capacity to connect new large industrial customers and as such, major The North Country transmission network is reinforcement to this system is planned. Heavy connected to the rest of the SWIS via very reliance is placed on the use of generating long 132 kV transmission lines. The North plant at Mungarra and Geraldton to top up Country load area is located north of the Perth transmission capacity to meet the load demand. metropolitan region, stretching from Pinjar and Western Power plans to continue using this Muchea to Kalbarri. The load area extends into generating capacity until major transmission the northern areas of the Wheatbelt, around 150 reinforcement works are delivered. km east of the coast. The load area supplies a range of mining and industrial loads, as well as Figure 60 shows the forecast load demand many rural centres and the main population of within the North Country load area. The graph Geraldton. does not include Western Power’s contract customers that are expected to rapidly The North Country network was designed to increase demand following reinforcement of the supply relatively small loads distributed over transmission network from Perth to Geraldton. a large geographical area. It is currently not capable of transferring large amounts of power Figure 61 shows the existing load area and its due to thermal, voltage and synchronous substations and transmission lines as of Q4 stability limitations. These constraints have 2008.

Figure 60: North Country forecast five year load demand.

300

250

200

150 MW & MVA 100

50

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 112

Figure 61: North Country load area Q4 2008.

Chapman

Durlacher St Geraldton

Mungarra Golden Grove

Rangeway Walkaway Windfarm

Eneabba Three Springs

Emu Downs 1 Moora To Wongan Hills Emu Downs 2

Kerr McGee Cataby Cataby Regans

To Pinjar To Pinjar To Muchea

The following projects in the North Country load in the area north of Chapman are expected to area were completed in 2008: further increase load growth at this substation. • Eneabba substation – second voltage Forecasts indicate there will be a significant regulator for Jurien feeder shortfall in the firm capacity at Chapman substation by summer 2009/10. • Geraldton substation – Narngulu West feeder extension to Dongara area This project will install a second 132/11 kV transformer, a new indoor switchboard and 5.13.1 Approved projects – North Country operate the Geraldton to Chapman line at 132 kV. It also includes the conversion of the Chapman substation – underground feeder present 33 kV line from Geraldton to Chapman to Waggrakin to operate at 132 kV by creation of a new Residential developments such as Glenfield Rangeway-Chapman 81 line. Installation of a 132 kV circuits at Chapman and Rangeway Beach estate and Bayside subdivisions have substations will allow for creation of the 132 kV diminished capacity of the existing feeder from line from Rangeway to Chapman. the Chapman substation. This project will install a double termination at Chapman substation This project is scheduled to be completed by with 5 km of underground cable to run along Q4 2009. West Coast Highway. Rangeway substation – install second This distribution project is scheduled to be transformer completed by Q1 2009. Rangeway substation has one 33 MVA Chapman substation– install second transformer. In 2009, feeders from Durlacher transformer Street substation will need to be transferred to Rangeway substation to avoid transformer Load growth at Chapman substation is growing overloading at the Durlacher substation. This will at 6% per year, with the substation capacity result in a significant deficiency in firm capacity nearly reached. New residential subdivisions at Rangeway substation.

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This project requires the installation of a 5.13.2 Regulatory Test submissions – second transformer and indoor switchboard at North Country Rangeway substation. Construct Chapman to Northampton 132 This project is scheduled to be completed by kV line Q4 2009. New land subdivisions, natural load growth Eneabba substation – install third and possible block loads in the Kalbarri transformer and Northampton region will contribute to considerable future growth. Eneabba substation has two 132/33 kV transformers. Due to unexpected increase To provide for a shortfall in capacity in the load growth in the area, there is insufficient Kalbarri and Northampton region, the following firm capacity at Eneabba substation for the options are being considered: forecasted electricity demand. This project will 1. Construct Chapman to Northampton 132 kV install a third 132/33 kV transformer and indoor line (initially energized at 33 kV). switchboard at this substation. 2. Construct 132 kV line from Chapman to Northampton and advance construction of This project is scheduled to be completed by 132/33 kV substation at Northampton. Q4 2010. 3. Construct 132 kV line from Chapman to Rudds Gully – establish new substation Oakajee (initially energized at 33 kV) and 33 kV feeder from Oakajee to Northampton. The distribution capacity to supply growth in the Southern Geraldton and Dongara areas will be 4. Construct 33 kV Chapman to Northampton exceeded by summer 2011/12. Furthermore, feeder (followed by transmission solution). supply capacity at Geraldton substation will 5. Construct 33 kV Chapman to Northampton diminish following the future withdrawal of feeder (followed by distribution solution). the Geraldton gas turbine. This project will 6. Construct 132 kV line from Chapman to construct a 132/33 kV substation to support the Oakajee and from Oakajee to Kalbarri, and Geraldton area. construct a 132/33 kV substation at Kalbarri.

This project is scheduled to be completed by 7. Demand side management. Q4 2011. 8. Network generation support.

Town of Kalbarri from the air. Photo Tourism Western Australia.

2009 Transmission and Distribution Annual Planning Report 114

Western Power’s option assessment currently Western Power will attempt to provide a indicates that a Chapman to Northampton Regulatory Test submission during Q2 2009. 132 kV line (initially energized at 33 kV) is the This project is scheduled to be completed by preferred solution. Q4 2011.

5.13.3 Future development projects – North Country

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Load growth in north Installing a 11 kV feeder Distribution Q1 2009 Geraldton approaching from Rangeway into capacity Spalding

Capacity at Kalbarri is Install dynamic reactive Distribution Q1 2010 limited by voltage drop compensation on the Kalbarri feeder

Capacity at Lancelin is Install two voltage regulators Distribution Q1 2010 limited by voltage drop on the feeder to Lancelin

Load growth at Kalbarri is Install second 33 kV feeder Distribution Q4 2011 approaching capacity to Kalbarri

Combined load in Geraldton Construct 132 kV Rudds Combined Q4 2012 area exceeds firm capacity Gully to Moonyoonooka line of existing transmission network

Capacity at Jurien Bay is Install second 33 kV feeder Distribution Q4 2012 limited by voltage drop to Jurien Bay and install new voltage regulator

Load growth in Southern Install second 132/33 kV Combined Q4 2012 Geraldton and Dongara transformer at Rudds Gully areas substation

Load growth on the 11 kV Installation of 33/11 kV Combined Q4 2012 network in the Southern transformers at Rudds Gully Geraldton area substation

Load growth in Mid West Convert second Pinjar to Combined Q4 2014 area exceeds capacity Geraldton line to 330 kV

Load forecast around Mid Regans substation re-supply Combined Q4 2014 West area exceeds capacity (relocation to Sappers Road) requiring conversion of second Pinjar to Geraldton line to 330 kV

Load growth around Establish a new substation Combined Q4 2014 Wongan Hills exceeds at Wongan Hills capacity of existing feeders

Load growth at the Wongan Install second transformer at Combined Q4 2013 Hills substation exceeds Wongan Hills substation capacity

2009 Transmission and Distribution Annual Planning Report 115

Figure 62: North Country load area Q4 2013.

Oakajee Moonyoonooka Northampton Chapman Terminal

Geraldton Golden Grove Durlacher St

Mungarra Walkaway Rangeway Windfarm

Rudds Gully Three Springs

Eneabba Eneabba Moora Emu Downs 1 Terminal

Wongan Hills Emu Downs 2

Kerr McGee Cataby Cataby Regans

To Pinjar To Pinjar To Neerabup To Muchea Terminal

5.13.4 Future outlook – North Country Northampton 132 kV line, and additional reinforcement to support load growth may Load growth exceeding the capacity limits be required. However, firm information on of the distribution network may require the load growth at Oakajee Industrial Estate is not establishment of substations in the following available at present. Supply to Oakajee may locations by 2020: eventuate from the future Moonyoonooka • Northampton Terminal by a 132 kV or 330 kV transmission • Drummond line. Western Power is planning to initiate the • Jurien Bay selection of a new line corridor to accommodate up to two double circuit transmission lines, • Dongara. with a voltage of up to 330 kV, between There are a number of uncertain customer- Moonyoonooka Terminal and Oakajee to driven developments which are not displayed. cater for potential growth. The scope of this These include windfarms which may require the reinforcement has not been finalised and will construction of a new 330 kV terminal station in depend on load growth at Oakajee Industrial Badgingarra, and a 400 MW coal-fuelled power Estate. station near Eneabba. Figure 63 shows the future 2020 view of the Oakajee Port and Oakajee Industrial Estate North Country load area and the developments will be initially supplied by the Chapman to which could occur based on current forecasts.

2009 Transmission and Distribution Annual Planning Report 116

Figure 63: Future outlook – North Country.

Oakajee Moonyoonooka Northampton Chapman Terminal

Geraldton Golden Grove Durlacher St

Mungarra Walkaway Rangeway Windfarm Dongara Rudds Gully Three Springs

Eneabba Eneabba Moora Emu Downs 1 Terminal Wongan Hills Emu Downs 2

Jurien Bay

Kerr McGee Cataby Cataby

Sappers

To Pinjar To Pinjar To Neerabup To Muchea Terminal

2009 Transmission and Distribution Annual Planning Report 117

5.14 Guildford and local residential subdivisions. As there is still much vacant land in the area, rapid load growth The substations in the Guildford load area appears likely to continue. The forecast growth supply a mixture of commercial, industrial and rates for substations in the Guildford Terminal residential customers with peak load occurring load area are approximately 7% average across during summer. the five years. Many substations in the area have experienced Figure 64 shows the forecast load demand rapid load growth over the last five years due within the Guildford load area. to increased land development activity. In particular, the area supplied by Midland Junction Figure 65 shows the existing load area and its substation and Forrestfield substation have substations and transmission lines as of Q4 experienced higher load growth due to new 2008. commercial loads from Westralia Airport, BCG

Figure 64: Guildford forecast five year load demand.

300

250

200

150 MW & MVA 100

50

0 2009 2010 2011 2012 2013

MW MVA Year

2009 Transmission and Distribution Annual Planning Report 118

Figure 65: Guildford load area Q4 2008.

To Northern Terminal

Guildford Terminal To Northern Terminal

To Southern Terminal

Forrestfield Midland Junction

Darlington To Northam

Kalamunda

The following projects in the Guildford load area Kalamunda substation – install third were completed in 2008: transformer • Uprate of Cannington Terminal existing Kalamunda substation supplies predominantly feeder circuit to 630A at Midland Junction residential customers growing steadily at substation; 2.4% per year. It is forecast that Kalamunda • Construction of a 132 kV line from Guildford substation will reach its capacity by December Terminal to Midland Junction. 2009.

5.14.1 Approved projects – Guildford As there is no neighbouring substation to support the growth at Kalamunda, a third 33 Forrestfield substation – install third transformer MVA transformer is required to meet customer demand. Forrestfield substation predominantly supplies industrial and commercial customers. Growth This project is scheduled to be completed by has generally been low until recently when Q4 2009. loads were transferred from Midland Junction Darlington substation – install third and Kalamunda. Major commercial and transformer industrial developments are in progress and it is necessary to expand this substation’s capacity Darlington substation supplies predominantly to cater for an expected increase in demand by residential customers. Load growth has Q2 2009. increased steadily at 3.4% due to new Forrestfield substation requires a third 33 MVA residential lot releases in the area. The transformer and indoor 22 kV switchboard substation will reach its capacity limit by Q4 to avoid thermal overload on the existing two 2009. transformers. A third 33 MVA transformer at Darlington This project is scheduled to be completed by substation is required to meet customer Q2 2009. demand in the area.

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This project is scheduled to be completed by Northern Terminal – Hazelmere line uprate Q4 2009. Strong forecast load growth at Hazelmere and Hazelmere – establish new substation Midland substations is expected to increase the loading on the Guildford Terminal 132 kV lines. Hazelmere substation is required to offload Under an outage of the Northern Terminal to load from Midland Junction substation. Midland Guildford Terminal 132 kV line and the Guildford Junction is expected to exceed capacity by Q4 330/132 kV transformer, the Northern Terminal 2009. to Hazelmere 132 kV line will approach its A new substation at Hazelmere will thermal constraints. In order to support the accommodate: increased load growth under these contingency conditions, the Northern Terminal to Hazelmere • development for a new police operations line is required to be uprated. complex near Midland railway station; • increased load demand in Hazelmere area This project is scheduled to be completed by due to recent rezoning as an industrial area; Q4 2011. • expansion of Midland Gate shopping centre; Cannington / Guildford Terminal load area • general load growth arising from the Midland 132kV fault uprate area. The connection of new generation and The substation will initially consist of a 33 MVA increased loadings on the 132 kV transmission transformer and two 5 MVAr capacitor banks. lines are increasing the fault levels at Cannington and Guildford Terminals. A number of This project is scheduled to be completed by components are approaching their fault levels Q4 2009. and are required to be uprated to 40 kA to meet Munday – establish new substation safety and reliability standards.

Munday substation will be established within This project is scheduled to be completed by the Westralia Airport to provide supply to future Q4 2011. major commercial and industrial developments 5.14.2 Regulatory Test submissions – within the Westralian Airports Corporation land Guildford holding. The substation will initially consist of a 33 MVA transformer and two 5 MVAr capacitor Reinforcement of Guildford network banks. Major commercial and industrial developments This project is scheduled to be completed by within Perth Airport land holding will overload Q4 2009. the existing Guildford terminal to Forrestfield 132 kV line, following a single line outage in the Hazelmere substation – install second area. With an extra 40 MVA of load forecast for transformer the Perth Airport within the next 10 years, it is Hazelmere substation is forecast to reach necessary to reinforce the transmission system. its capacity by Q4 2010. It is used to To provide adequate reliability for new accommodate the Goodman development customers, the following options are being block loads, and the 75% NCR wind back in considered: transformers in the Guildford Terminal area. 1. construct a Guildford to Forrestfield 132 kV A second 33 MVA transformer at Hazelmere line; substation is required to meet customer 2. construct a Guildford to Kalamunda 132 kV demand in the area. line; This project is scheduled to be completed by 3. construct a Cannington to Kalamunda/ Q4 2011. Munday 132 kV line;

2009 Transmission and Distribution Annual Planning Report 120

4. construct a Cannington to Kalamunda/ will maximise the net benefit after considering Mundaring Weir 132 kV line; all available options. However, detailed option 5. demand side management; analysis has not yet been completed. 6. local generation. Western Power anticipates that a regulatory submission will be presented in Q4 2009. Studies to determine the best economic option are currently being assessed. Western Power The project is scheduled to be completed by Q4 presently believes that the construction of a 2010. Cannington to Kalamunda / Munday 132 kV line

5.14.3 Future development projects – Guildford

Constraint Recommended Transmission / Forecast Reinforcement Distribution Energisation Date

Under-rated distribution Network extension and Distribution Q4 2011 conductor in the Darlington reinforcement from network Darlington substation

Insufficient capacity for Network extension and Distribution Q4 2013 power demand in Midland reinforcement from Midland Junction area Junction substation

Load growth exceeding Install third transformer Combined Q4 2014 capacity at Munday substation

Figure 66: Guildford load area Q4 2013.

To Northern Terminal

Guildford Terminal To Northern Terminal

Hazelmere

To Southern Terminal

Forrestfield Midland Junction

Darlington To Sawyers Valley

Munday Kalamunda

To Cannington Terminal

2009 Transmission and Distribution Annual Planning Report 121

Figure 67: Future outlook - Guildford.

To Northern Terminal

Guildford Terminal To Northern Terminal

Hazelmere

To Southern Terminal

Forrestfield Midland Junction

Darlington To Sawyers Valley

Munday Kalamunda

To Cannington Terminal

5.14.4 Future outlook – Guildford Due to the current ongoing discussions with the WAC customer about the financial support for The Westralia Airport Corporation (WAC) Perth the Munday substation, the project is currently airport expansion project will be the only major still pending. However, it is expected that the new development in the Guildford load area. This Munday substation should be operational within project will require the establishment of the the next 10-15 years to support the load growth Munday substation, which will offload most of the in the Forrestfield and Munday load areas. airport load from the Forresfield substation. The Figure 67 shows the future 2020 view of Munday substation is scheduled to be completed Guildford network and how it is forecast to by October 2009. develop.

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2009 Transmission and Distribution Annual Planning Report 123

6 Other planning issues

Western Power follows a rigorous consultative approach to obtaining approvals for all infrastructure projects.

6.1 Sustainability of high conservation value (for example, national parks, nature reserves), existence of Western Power has adopted a company wide rare, protected or threatened flora, impact on sustainability policy articulating our commitment fauna and their habitats, and issues related to contribute to the challenges of sustainable to watercourses, water catchment areas and development. The sustainability policy includes wetlands. a set of principles that set priority focus areas for our approach. Western Power, the community and other stakeholders, consultants and regulatory The policy assists to embed sustainability criteria authorities examine and balance these issues. in all phases of the infrastructure project life This information is used in submissions to cycle and ensures alignment with stakeholder obtain mandated approvals such as those and community expectations. Western Power’s required under the Access Arrangement, the aim is to undertake an ethical and sustainable Environmental Protection Act and the Planning works program through the application of and Development Act. sustainability assessment methodologies that underpin our policy. 6.1.2 Environmental management The Environment and Land Management Western Power is committed to protecting (ELM) Branch is responsible for managing the the environment and continuing to improve its community consultation process, obtaining environmental performance. all necessary environmental and planning approvals and negotiating land easements To deal with its many and varied environmental where required. impacts, Western Power has established an Environmental Management System (EMS). 6.1.1 Planning checklist The EMS is a structured process for achieving Western Power considers many issues when continuous improvement in environmental selecting its projects and suitable line routes performance. or sites for other electricity infrastructure. An important part of the EMS is Guardian, These include economic, technical, social and Western Power’s new online system for environmental factors: reporting and managing environmental • Economic – this involves assessing the cost incidents, hazards and their related and value of various options. recommendations.

• Technical – this considers the impact of The new system is easy to use and allows issues such as line losses, energy efficiency, Western Power to comply with a range of demand side options, access, hydrology, legislative and due diligence requirements. river crossing, and existing and planned infrastructure solutions. The foundation of Western Power’s EMS is its environmental policy. In 2009, Western Power • Social – this addresses community issues, will release a revised environmental policy to visual impact, proximity of homes and reflect its commitment to operating the network businesses, cultural issues and impact on sustainably; delivering electricity in a manner land use. that meets community needs and expectations. • Environment – this looks at proximity to It builds on the successes of previous policies environmentally sensitive areas or areas and establishes a range of strategies and

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actions, many of which go beyond standard inform affected stakeholders of its business environmental compliance. activities and where possible, involve them in the decision-making process. For example, In accordance with our environmental residents and local governments provide input policy commitment to ensure environmental into line route selection and landscaping plans considerations form part of our business surrounding new substation sites. planning and decision-making processes, new capital projects are assessed for their Stakeholders that may be affected by Western environmental impact. A thorough environmental Power projects vary, but typically include: management process is then followed to ensure • relevant government agencies; that all issues related to the environment are fully • local government; considered and addressed. • community and special interest groups; This process involves liaising with stakeholders • Indigenous groups; regarding environmental issues that have been • environment groups; identified and commissioning necessary surveys • local Members of Parliament; and to address environmental and heritage uses. • residents, landowners and businesses. An Environmental Management Plan is then developed to manage the identified issues. The method Western Power uses to engage with its stakeholders varies depending on the All construction activities are required to comply type of stakeholder and the complexity of the with the Environmental Management Plan. A issues surrounding a project. Communications post-construction audit of any environmental used to inform and/or engage with stakeholders conditions is undertaken, and if required, include: remediation work carried out. • information briefings (by invitation or open 6.1.3 Stakeholder engagement forums); • community workshops; Western Power aims to partner with the • individual briefings, for example, to local community when planning its power solutions Members of Parliament; and be responsible to the people who live, and businesses that operate, near its assets. • regular newsletters; • newspaper advertising; In planning large transmission projects, • radio interviews; Western Power consults extensively with local communities and other stakeholders • door knocking at individual residents and to identify and address potential constraints. businesses; For all its projects, Western Power seeks to • website updates; and

Possum Power program.

2009 Transmission and Distribution Annual Planning Report 125

• displays at local shopping centres, halls, any special environmental considerations prior to libraries and other community centres. attending a site and undertaking works, ensuring compliance with environmental legislation and 6.1.4 Environmental strategy stakeholder requirements.

A range of innovative initiatives have been When new infrastructure is designed to traverse developed to reflect Western Power’s an environmentally sensitive area, management environmental strategy to promote sustainable strategies are developed and included in the development across the business. Some are project’s Environmental Management Plan. listed below: These strategies ensure that conservation values will not be compromised during construction Environmentally Sensitive Area program works. Once the infrastructure is operational, the (ESA) area of conservation value is included in the ESA Established in 1996, the ESA program was program for protection. developed to ensure Western Power and its activities did not compromise existing Carbon Neutral Program conservation values of an area. In 2007, Western Power successfully launched its Carbon Neutral Program and planted 93,000 ESA signage. native seedlings to offset the greenhouse gas emissions from its fleet vehicles and mobile generating facilities.

Cannington substation site.

In 2008, Western Power expanded this successful program by planting a further 150,000 native seedlings to offset 40,000 tonnes of carbon emissions from its fleet vehicles, mobile generating facilities and 2% of its annual line losses.

The program addresses environmental This program is carried out through Carbon issues such as declared rare flora and fauna, Neutral, a company founded by Men of the threatened ecological communities, biosecurity Trees, which was established in 2001 to involve threats such as weeds and diseases and more the community and industry in responsibly recently organic farms and those suffering from offsetting greenhouse gas emissions from their multiple chemical sensitivity. business activities.

This program ensures that Western Power employees and contractors are made aware of

2009 Transmission and Distribution Annual Planning Report 126

Carbon Neutral Program. Greenhouse Challenge Plus Program

Western Power is a member of the Greenhouse Challenge Plus Program, a cooperative partnership between industry and the Australian Government with a principal objective of putting appropriate, practical and cost-effective actions in place to meet the challenges of climate change and reduce its greenhouse gas emissions.

Through this program, Western Power has committed to abate greenhouse gas emissions by: • investigating options to reduce line losses from the transmission and distribution network; • implementing a monitoring program to reduce emissions of sulphur hexafluoride, a greenhouse gas used in electrical equipment; and Bibbulmun Track Foundation • implementing a program of vehicle fleet Western Power has committed to sponsor initiatives that improve energy efficiency and the Bibbulmun Track Foundation, a not-for- use more greenhouse friendly fuel sources. profit organisation formed in 1997, to provide Western Power will continue to examine community support for the maintenance and opportunities to abate greenhouse gas promotion of the 980 km Bibbulmun Track. emissions and address climate change issues.

This sponsorship is significant, as our electricity Centre for Phytophthora Science and supply network intersects with the Bibbulmun Management Track at more than 70 locations. Western Power has committed to contribute Our three year sponsorship will improve the to the important research efforts of the Centre provision of training and resources to staff and for Phytophthora Science and Management. volunteers of the Bibbulmun Track Foundation The Centre’s research aims to halt the spread and ensure the Bibbulmun Track remains a of Phytophthora dieback, which is vital to quality walking trail of international standard. preserving the State’s biodiversity.

Bibbulmun track signage. To address this major biodiversity threat, Western Power regularly conducts surveys and develops management plans to avoid Phytophthora dieback infected areas and complies with forest hygiene requirements for new capital works.

Policies and procedures are also in place to restrict the movement of soil and plant life during construction and maintenance activities, which minimises the risk of spreading Phytophthora dieback.

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6.2 Communications network systems. This physical duplication extends to the communications links at the site. Each site 6.2.1 Western Power communication must be connected by at least two physically technologies diverse bearers.

Western Power is committed to providing a A growing number of Tee’d line configurations in robust, flexible communications network. The Western Power’s network has increased the use recently introduced regulatory and electricity of digital differential protection schemes. This market framework places higher reliance on type of protection requires each site to compare available, accurate and timely data. Western current and voltage waveforms with the other Power has correspondingly improved stringency sites. High-speed digital communications in design to ensure: links in a mesh configuration are required to • high circuit availability; achieve adequate protection. Duplicated digital differential protection on a Tee’d line places • provision for redundant paths; special requirements on the communications • a fibre-optic cabling-based solution as the network. In addition to the two physically first preference; and diverse bearers required in a two-ended line, a • a suitable environment for communications Tee’d line arrangement requires a third physically equipment. diverse bearer path between two of the three sites. Development of the communications network is primarily driven by transmission network 6.2.3 SCADA (Supervisory Control and augmentation, however the communications Data Acquisition) network is heavily influenced by rapid changes in communications technology and the relatively SCADA functions as the monitoring system short asset life of communications equipment. used by operators. Without SCADA, operators would have to be dispatched for every switch Communications are necessary to ensure operation and to check the status of every item the safe, efficient and reliable operation of of plant at Western Power’s substations and the electrical network. The communications terminals. SCADA remote terminal units (RTUs) requirements flow from three basic areas, are installed at sites to monitor plant status, Protection, SCADA and Operations. report alarms, record current and voltage and to operate circuit breakers and other plant. RTUs 6.2.2 Protection are connected back to the SCADA Master Station at East Perth Control Centre and to the Protection of Western Power’s electricity back up master stations at the head office and network requires the fast detection and isolation Southern Terminal. of electrical short circuits. In order to minimise damage to transmission lines and transformers A dedicated analogue or digital circuit is required in the event of an electrical fault on the network, for SCADA, and RTUs at critical sites require a means of isolating the fault is necessary. a physically diverse duplicate communications On critical lines, the fault has to be precisely connection. identified and cleared to maintain network stability. Only the line affected must be taken out 6.2.4 Operations of service to avoid unnecessary interruption to Telephones are required for safe operation of Western Power customers. electricity sites. Remote condition monitoring To enable the protection scheme to quickly and work efficiency are driving the requirement identify and clear faults on two-ended lines, for corporate LAN at substations and terminals. protection relays at opposite ends of the line Fault recorders that store large quantities of are connected with one or more analogue or power quality data require LAN access for digital communication links. Except for very quick data retrieval. The engineering officers long lines, the protection systems are typically need access to email, electronic drawings and duplicated, using two completely independent software databases while on site.

2009 Transmission and Distribution Annual Planning Report 128

Figure 68: Microwave and fibre optical fibre communications network.

2009 Transmission and Distribution Annual Planning Report 129

6.2.5 Choice of bearer Experience has shown that Perth’s weather exhibits two characteristics that degrade the Western Power has a number of bearer viability of microwave: options to use to support the communication requirements of a project. The decision as to • the presence of dense rain micro cells where which bearer to use is influenced by a several rainfall is concentrated at much higher factors. These include: densities than average figures would indicate. • the cost of the bearer; In combination with the typical south west orientation of incoming storm fronts this • the nature of the project; results in regular ‘rain fade’ outages for • proximity of existing communications microwave links oriented on a north west to facilities; and south east line; and • requirements of other projects in the vicinity. • the known tendency for sub-refractive Where possible the communications bearer ducting along the coast from Perth to is selected to form a strategic link in the Carnarvon. This weather anomaly regularly communications network that creates a platform takes the microwave out of service for for connecting related or future projects. periods ranging from minutes to hours. Western Power’s most common bearer options are detailed below: Both these outages tend to occur at times of maximum stress for the electricity network, and Optical fibre for that reason a weather immune bearer such as optical fibre is the preferred solution for at Optical fibre is the preferred communications least one of the bearers into each critical site. bearer for a number of reasons. It is intrinsically dielectric and is immune from electrical There is also increased difficulty in obtaining disturbances and magnetic fields, making planning approval for microwave towers. it ideal for electricity sites. Optical fibre is Environmental Land Services reports ever- immune to radio frequency interference and increasing community resistance to siting weather anomalies that affect microwave radio microwave towers. This is due to the increasing communications. Fibre offers virtually unlimited public sensitivity to the proliferation of towers bandwidth and can be buried or installed on initiated by the mobile phone rollouts, and overhead power lines. to the concern about the health effects of electro-magnetic radiation from the antennae. Including fibre during new line works is the Microwave’s main advantage is that the least expensive option for installation. Western hardware is required only at the ends of the link Power has installed buried optical fibre so intervening easements or right-of-ways are while distribution undergrounding works are not required. underway. Including optical ground wire (OPGW) in a new line build incurs only an incremental Western Power’s Microwave and optical fibre increase over the cost of the overhead earth communications network is shown in Figure 68 wire (OHEW). The disadvantage of optical fibre on the previous page. is the cost when the installation cannot be leveraged off works that are underway. Pilot cable

Microwave The Western Power pilot cable network is a legacy of early protection relays. Pilot cable is While Western Power still maintains an typically 40-core copper with a steel armour extensive microwave radio network, the reliance jacket. This poses a number of concerns. of microwave has been reduced over recent years. This is because of limitations inherent in It requires elaborate and costly treatment at the technology. each electricity site to avoid earth loops and inducted voltages damaging equipment. Sectionalising transformers are required at

2009 Transmission and Distribution Annual Planning Report 130

each node for each circuit, requiring substantial circuits on a ‘best efforts’ basis that do not meet wall space in substation control rooms. The the availability requirements adopted by the cable also supports only very low bandwidth National Electricity Rules in the Eastern states. requirements and will not reliably run even ‘Best effort’ service delivery means: minimal digital services further than 10 km. • Carriers do not provide a guaranteed The intrinsic hazards entailed mean that specific availability of service; inductions and qualifications are required to • Carriers do not guarantee a minimum work in the pilot cable enclosures, qualifications restoration time; that only a small number of Western Power • Carriers do not announce or coordinate employees possess. At present there is scheduled circuit outages; and an extensive pilot cable network installed • Carriers do not guarantee or even release connecting most metro substations. details of circuit routing (in the instances Power line carrier where physical diversity is required).

Western Power has only one power line carrier, 6.3 State Underground Power on the Merredin Terminal to West Kalgoorlie Program (SUPP) 220 kV line. The power line carrier uses the transmission line as the communications In 1994, severe storm damage to the overhead bearer to provide a small number of low distribution system left many thousands of speed voice or data services and protection. customers in the metropolitan area and the A power line carrier link is roughly the same south-west region without power for several cost as a microwave link, and a single link days. As a result, the State Government can span a much greater distance compared established a Steering Committee comprising with microwave technology. However, this representatives of the Office of Energy, technology offers only half a dozen circuits Western Power and the WA Local Government rather than the hundreds offered by microwave Association, to investigate undergrounding the and thousands offered by optical fibre. overhead distribution system. Undergrounding Existing practices allow two independent power of the transmission system was not included line carrier systems to carry duplicate protection due to the very high costs and its robustness over the same transmission line, but this against damage. A pilot program of five projects practice is under review, and it appears likely to started in 1996 established the technical and be deemed unacceptable for future installation. financial viability of undergrounding local power lines. In 1996, the Government established Carrier services (such as Telstra and Optus) two strands to the program – major residential Western Power makes wide use of carrier- projects and the smaller localised enhancement leased lines for voice services and for projects with a commitment to having half connection to SCADA RTUs where no the Perth metropolitan area serviced by communications bearer exists. Carriers provide underground power by the year 2010. This

Figure 69: Key process map.

Maintain

Manage Plan Design Procure Build & Monitor

Operate

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target is to be achieved by the combination of 6.4 Reliability improvement program the program and new property subdivisions that must only use underground power. Western Power’s reliability improvement plan establishes solid and robust business rules Each major residential project is funded jointly and processes for the effective, practical, cost by the State Government, Western Power and effective and efficient delivery of reliable power by the relevant local government. The base cost to all Western Power customers. In order to is around $8,000 to $9,000 per electrical meter ensure that reliability performance is constantly for 1,000 to 1,500 meters in a typical project. monitored and improved, it needs to be Local governments usually fund these projects recognised that governance and management through rates on property owners. systems must be established to:

For localised enhancement projects the cost is • identify process/systems gaps; about $650/metre and the State Government • introduce and manage change; and and Western Power equally fund up to • develop and enhance systems, processes, $250,000 on a dollar per dollar basis with the procedures and resources. local government. The reliability improvement plan is applicable The program has completed 34 major to all processes that fit within the key process residential projects, costing $193 million and of delivery of electricity to Western Power’s undergrounding power to 61,000 electrical customers. The key process map is represented meters – about 13.8% of the original overhead below. distribution system. This has been achieved The plan aims to establish management and through the pilot (five projects), round one governance frameworks for issues relating (eight projects), round two (twelve projects) and to power reliability, including, but not limited round three (nine projects). Some 23 localised to, processes, measurements, equipment, enhancement projects have now also been structures, communication systems and completed, involving $7.6 million expenditure customer/stakeholder expectations. and undergrounding approximately 19 km of overhead lines in focal areas of communities. The reliability improvement program consists of a number of distribution projects as described Como East is the last of the round three major residential projects and commenced below: in April 2008 along with the first two round 40 worst feeders program four projects, Mount Pleasant North (February 2008) and Palm Beach (October 2008). The The 40 worst feeders program is a maintenance last round three localised enhancement project program which targets feeders that contribute was completed mid 2008 and the first project in the most towards SWIS SAIDI across the round four, Toodyay, commenced in June 2008. South-West Interconnected System. A list of 40 worst feeders was selected for every financial The remaining five major residential projects in year for the period 2005-06 to 2007-08, round four will commence progressively from resulting in a total of 120 feeders chosen for the February 2008 to July 2010 and the remaining entire period. seven local enhancement projects, Brunswick Junction, Cowaramup, Bunbury, Jurien 119 of these feeders have been inspected Bay, Victoria Park, Bayswater and Belmont and maintenance conditions identified. These commencing progressively from March 2009 to identified conditions are currently due for October 2010. completion by the 2009/2010 financial year.

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Rogue feeder program Distribution automation

This maintenance program targets metropolitan Western Power is continuing with the targeted feeders that have a high number of customer reliability driven automation roll-out. This interruption minutes, but not necessarily works program consists of the installation contribute highly towards SWIS SAIDI. of distribution automation equipment that will further assist in improving the network A total of 60 feeders (20 per year) were selected reliability by reducing the number of customers as part of this program for 2005-06 to 2007- affected per fault via sectionalising and remote 08. These feeders have all been inspected and remedial works are expected to be completed restoration. during 2008/2009. The equipment includes remotely controlled and Targeted reliability reinforcement monitored reclosers, pole-top switches, fault indicators, voltage controllers and capacitor This capital works program targets feeders banks. The equipment allows operators in the which contribute the most towards SWIS SAIDI. East Perth Control Centre to quickly identify It includes activities such as upgrading of wood faults, remotely operate switches to isolate poles and crossarms, installation of surge the faulted line section and reconfigure the diverters and wildlife proofing devices, replacing network to restore power around the faulted bare open aerials with covered conductor and line to minimise the extent of an outage. The minor undergrounding works. Approximately operators can also remotely monitor and adjust $18 million has been budgeted for this work in line voltage by changing capacitance values and 2008/09. transformer settings. Emergency response generators Western Power is rolling out radio-based A total of 11.5 MVA of emergency response infrastructure to allow data communications to generation has been secured for the 2008-09 these distribution automation devices. Radio summer period. Approximately 6.5 MVA is bases are being installed at strategic locations available for the entire year (as part of the Base in both metro and country locations to provide Management Fleet). An additional 5 MVA is coverage to the pole mounted distribution available during the summer period to cater automation devices. for increased fault activity, as well as providing The 2008/09 automation program consists of contingency coverage for projects that may not meet their required implementation dates. approximately 300 projects, of which around 170 are new devices such as reclosers and The base fleet now includes four units (totalling load-break switches, 50 are upgrades of 1.2 MVA capacity) available for country use. outdated hydraulic switchgear (to enable them These will be located in major country towns for telemetry and remote control), as well as the once all operational training is completed, and retro-fitting of telemetry to around 80 existing should improve fault response times in the devices in the network. country areas. Sequence switching Rural power improvement program Sequence switching is a pilot project, which This program targets projects that will provide aims to improve network reliability and to measurable improvements in electricity supply in maintain a consistently optimised level of supply rural areas where reliability is unsatisfactory and restoration performance. It allows the network not likely to be addressed through any other to automatically monitor itself and after a Western Power program of work. sequence of checks take measures to evaluate Approximately $22 million of reliability back-feeding feasibilities to enable partial or improvement projects is planned to be full restorations of supply within a matter of undertaken across rural networks in the North minutes. As the level of automation devices in Country and South Country regions in 2008/09. the network is optimised sequence switching

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is one of the main strategies that should not 6.6 Alternative generation only improve network reliability, but ensure a consistent level of performance is utilised Western Power is positioned to become an from existing devices. This will be due to the energy solutions business. We believe in remote restoration scripts automatically initiating creating a network that supports all types of based on a series of conditions or events being energy generation. Western Power attempts to met that do not rely on operator availability or provide access to the network for all generation intervention. proponents provided electricity supply can be maintained in accordance with the technical 6.5 Demand side management rules.

Regulatory provisions in the Electricity Networks Western Power encourages all forms of Access Code 2004 and the Wholesale sustainable generation to complement the more Electricity Market Rules 2004 require Western conventional base load power supply. Currently Power to consider alternative options as part the South-West Interconnected Network of the regulatory approvals process for network supports alternative generation from biomass, augmentation projects with the aim of optimising wind, solar and hydro plants. overall long term costs associated with supply Western Power is actively reinforcing the of electricity. The Economic Regulation Authority transmission network in strategic areas that will assess Western Power’s capital expenditure can accommodate all forms of conventional submissions within the Regulatory Test and alternative generation. Although the framework, having due regard for non-network exact location of future generating plant is options including demand side management. not determined by Western Power, it can Western Power is planning to implement the be influenced by the location of network second and third phases of the Nedlands/ infrastructure. Claremont air-conditioning direct load control Western Power welcomes enquiries and trial over the summer period in 2008/09 and applications for the connection of generation 2009/10 respectively. from renewable energy sources. It is anticipated that further demand side management trials will be implemented to establish the effectiveness of peak electricity demand reduction initiatives for improving the economic efficiency of network augmentation capital investments; to build internal capability to assess and implement demand side management as part of a portfolio of network capacity management solutions or options; and meet its regulatory obligations. These are likely to include the use of smart meters and smart grid technology to test the capability of this new infrastructure to support load control programs. Wind farm Albany.

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7 Abbreviations

APR Annual Planning Review

CBD Central Business District

DNSP Distribution network service provider

DSM Demand Side Management

DUOS Distribution use of system charge

EPA Environmental Protection Authority

ERA Economic Regulation Authority

ERTF Electricity Reform Taskforce

Firm Capacity A substation designed to the N-1 reliability criteria must be capable of withstanding the loss of any single transmission plant item comprising the substation transformer circuits at any load level without loss of load

IPP Independent power producers

kA Kilo Amperes (measure of electrical current)

kV Kilo Volts (measure of electrical potential)

MDP Metropolitan Development Plan

MVA Mega Volt Ampere (measure of electrical demand)

MW Mega Watts (measure of the active component of electrical demand)

N–0 For a substation to be designed to N-0 reliability criteria means all load supplied by the substation may be lost as the result of an outage on any single transmission plant item comprising the substation

N–2 N-2 criteria means the consequences of the coincidence of one planned and one unplanned outage of transmission elements, at or below 80% of peak load, will normally result in supply being maintained without loss of load, provided generation is rescheduled prior to the second outage

NCR Criteria A zone substation designed to the NCR reliability criteria allows for the loss of an amount of load equivalent to a transformer’s pre-outage loading at any load level ensuring the outage of any single transmission plant item comprising the substation transformer circuits. Loss of load is permitted for the period required to install the Rapid Response Spare Transformer (RRST)

PoE Probability of Exceedance

PPG Power Procurement Generator

SADI System Average Interruption Duration Index

SECWA State Energy Commission of Western Australia

SWIS South-West Interconnected System

TNSP Transmission Network Service Provider

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8 Appendix A – Introduction to network issues

8.1 Planning and operating Required performance will be related to electricity networks underlying economics:

Electricity networks are used to transport • In a CBD, for example, a fault or unplanned electricity from the power station to the outage on the transmission system should customer. The transmission network allows the not result in a loss of supply. The large bulk transport of power across long distances at number of customers connected to the high voltages. The distribution network delivers system justifies back-up systems. electricity from the transmission substation to • In a rural distribution network, however, a the end customer, usually over shorter distances fault may result in a loss of supply but this and at lower voltages. should be for a limited load and a limited The planning, design, operation, maintenance time. There will be contingency plans to and augmentation of electricity networks must restore supplies after a fault. The smaller ensure that each individual piece of network number of customers connected to a rural equipment is operated within its design limits. system is unlikely to justify extensive back-up This requires voltage and power transfer for systems. each asset to be assessed under a wide range • The quality of supply should be maintained to of potential conditions, including for example the appropriate standards. Quality of supply modelling the effect of faults on the network. is a term that embraces voltage, frequency This is illustrated in Figure 70 below. Failure and other technical aspects of power supply. to meet voltage design limits can result in malfunction or damage to customer equipment, • The potential for future growth should also be while exceeding power transfer limits creates adequately provided for, where economically potential safety and reliability hazards. viable to do so, ensuring that Western

Figure 70: Need for back-up facilities.

The network can withstand credible faults Power’s electricity networks do not impede and unplanned outages. A fault is considered Western Australia’s economic development. credible if it is considered likely given the This may mean, in some circumstances, prevailing circumstances. For example, a installing ‘larger’ plant than is immediately simultaneous fault on two adjacent circuits required, to cater for expected load growth might be considered credible in a severe storm, over the next 10 years or so. but not in normal weather conditions. If there is • Environmental impacts must also be a credible fault or unplanned outage, all plant responsibly managed. must still operate within its design limits and the network must continue to deliver its required performance.

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In planning and operating the system, it is Circuit breakers are used to switch out the important to distinguish between system faulted elements. Clearly, circuit breakers security and supply to individual customers. must be capable of interrupting the very high For example, the system is insecure, even if all currents safely. To this end, circuit breakers customers are currently being supplied, if there (and associated equipment) have fault current is a credible fault that would lead to widespread ratings. Complex calculations are carried out to loss of supply. The system is secure, even if identify the potential fault currents at different some customers are currently without power, if locations on the network, and the circuit the system can withstand a credible fault. The breakers installed must have a fault current most famous example of this paradox was in rating that is greater than the potential fault California in early 2001 where suburbs were current. subjected to rolling black-outs to maintain Similarly, all other network equipment must overall system security. Overall, a secure system have a fault withstand capability greater is likely to lead to more reliable supplies for than the potential fault current at its network customers. location. That is, it must be able to safely carry 8.2 Faults on electricity networks fault current, albeit for a very short time. The extremely short-lived nature of fault current A fault on the electricity network may be explains why plant can carry fault current many caused, among other things, by lightening times its rating in normal use. strikes, catastrophic failure of equipment, debris Two things primarily affect the potential fault falling on lines or vegetation touching lines. A current at a point on the network: the proximity fault will tend to result in: to generation and the impedance of the local • a very high current flowing towards the network. Fault current is ‘fed’ by generation, and location of the fault, many times the normal so the nearer the network element is to a power rating of the network equipment, known as station, the greater the potential fault current. the fault current; and Impedance can be described as an object’s • a very low voltage (tending towards zero) opposition to the flow of electric current. A low near the location of the fault. impedance network will therefore give rise to a high fault current, where a high impedance If a network fault was not addressed network will limit fault currents. immediately, it could eventually black-out the whole system. As such, networks are The isolation of faulted equipment will, generally, designed to immediately isolate the faulted increase flows on other network elements. If this network element from the rest of the network. contingency would overload another network For example, if a crane were to stray too close element, so-called ‘pre-contingent’ action will to a distribution line and cause a fault, the be taken. This means that the network will distribution line would be automatically switched be operated less efficiently to allow for the out of service. possibility of a contingency or fault.

Short-lived faults are known as transient faults. For example, a lightening strike will cause a temporary fault on the network. To ensure that equipment is not needlessly out of service, transmission equipment will automatically reenergise the network element after a short delay. This is known as ‘reclosing’. If the fault is still present, the network element will be automatically isolated once more. The network element will remain isolated until the fault has been investigated and repairs made.

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8.3 Meshed and radial networks Inter-tie feeders are used to provide fast restoration of supplies following faults. Following An electricity network is described as highly a fault, the affected network will be switched meshed when each substation is connected to out of service, and the normally open switch a number of other substations, as illustrated in energised. The switch is normally open as to the figure below. have it energised before the fault would give rise to very high fault currents. Figure 71: Highly meshed networks. 8.4 Peak demand, weather and diversity

Peak electricity demand may last for only a few hours. However, the network must be capable of supplying the maximum load that occurs.

The extent of simultaneous consumer demand affects peak demand significantly. For example, a bakery’s peak demand may occur overnight when it is in full production. During the day, its The main advantage of a highly meshed demand is likely to be low. On the other hand, network is clear – if line 1 were taken out of an office building would normally operate during service, substation A would still be supplied by business hours and shut down overnight. three other lines. The meshed network provides Maximum demand in an office building tends a secure supply. However, a network as highly to occur during the mid afternoon. This load meshed as that in the figure above would diversity is helpful to Western Power, as it tends also be extremely expensive to develop. This to reduce demand peaks and increases asset expense is often justified on the transmission utilisation. network. The figure below shows typical load profiles for A radial network is illustrated in the figure below. residential, commercial and industrial loads. Residential loads tend to peak later in the Figure 72: radial networks. evening towards 8 pm whereas commercial loads tend to peak in mid afternoon at approximately 3 pm. Industrial loads tend to ramp up in the morning and maintain a relatively constant output throughout the day, before decreasing demand in the mid-afternoon. A mixed residential/commercial profile is a reasonable composite of the residential and commercial profiles, where the peak depends on the mix of residential and commercial loads.

It can be seen that the radial network is While the underlying trend in peak demand may inherently less secure – if line 2 is lost, be steady, peak demand in any particular year is substation B would lose its supply. Nonetheless very sensitive to prevailing weather conditions. a radial network is much cheaper than Heating loads in winter and air-conditioning a meshed network and so is suitable for loads in summer are the two main influences distribution networks. Furthermore, a meshed on peak demand. On a particularly hot (or distribution network could give rise to very high cold) day, everyone turns on the air-conditioner fault currents. (or heater) at roughly the same time. This simultaneous consumption behaviour drives peak demand. Moreover, most air-conditioners

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are turned on during the hottest part of the day and turned off as the temperature declines in late afternoon, exacerbating peak demand – air- conditioning loads are described as having low diversity.

Figure 73: Typical SWIS load profiles of residential, commercial and industrial loads.

120

100

80

60 Percentage

40

20

0 0:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 Time of day Residential Commercial Industrial

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9 Appendix B – Substation load forecasts

This appendix presents detailed tables of load The forecasts do not represent maximum forecasts at each of Western Power’s South- demands that are coincident with overall West Interconnected System (SWIS) major SWIS peak demand but rather the expected nodes. maximum demand at each major node. Where there is embedded generation connected, The load forecasts are for the peak demand then the load forecast is on the basis that at each major node and are grouped based this generation is not operating at the time of on the bulk injection points for the geographic maximum demand. area. Western Power has prepared these load forecasts, in MW and MVA. The real maximum demand at any connection point in any year may vary from these load Where a major customer is associated with forecasts due to socio-economic factors, a node then the total of the load forecasts weather conditions (particularly temperature) is summarised in the Contract Customer and changes in network connectivity. group (refer to Table 10.14) irrespective of the geographic area where the customer is connected to the SWIS.

2009 Transmission and Distribution Annual Planning Report 142 0.00 MVA MVA 46.59 42.80 33.13 48.11 48.00 67.46 60.00 84.53 14.96 14.96 48.75 71.72 16.78 13.79 15.65 34.57 65.31 32.12 91.59 91.59 2013 2013 MW MW 0.00 41.00 37.27 29.81 42.85 41.28 59.59 51.19 72.69 13.29 13.29 46.64 63.86 15.88 12.82 15.22 32.51 58.48 29.81 86.29 86.29 0.00 MVA MVA 45.39 42.16 32.41 46.67 37.05 63.06 58.82 91.54 14.96 14.96 46.81 69.40 16.46 13.51 15.02 33.84 62.59 31.01 91.59 91.59 2012 2012 MW MW 0.00 39.94 36.71 29.17 41.57 32.24 55.71 50.18 78.73 13.29 13.29 44.78 61.79 15.58 12.57 14.61 31.83 56.04 28.78 86.29 86.29 0.00 MVA MVA 49.81 29.56 31.69 45.23 30.32 61.03 69.57 88.67 14.96 14.96 44.87 73.19 16.15 13.24 14.39 26.93 59.71 29.90 91.59 91.59 2011 2011 MW MW 0.00 43.84 26.31 28.52 40.28 26.38 53.91 59.01 76.26 13.29 13.29 42.93 64.43 15.29 12.31 13.99 26.13 53.47 27.75 86.29 86.29 6.43 MVA MVA 65.29 29.10 36.30 43.79 24.06 42.49 59.90 83.71 42.93 14.96 70.51 14.96 15.84 12.96 13.75 26.55 56.73 17.37 66.03 66.03 2010 2010 MW MW 5.47 57.45 25.90 32.67 39.00 20.69 37.67 52.33 41.07 62.07 71.99 14.99 13.29 12.06 13.29 13.38 25.77 50.79 16.13 63.29 63.29 6.43 MVA MVA 68.77 28.65 33.88 40.75 40.99 23.26 67.82 41.09 15.53 58.56 12.69 13.12 80.03 26.18 14.96 53.72 14.96 14.75 66.03 66.03 2009 2009 MW MW 5.47 60.52 39.22 25.50 59.70 30.49 14.70 36.30 11.80 20.00 12.76 36.43 25.41 51.16 48.10 13.70 68.83 63.29 13.29 63.29 13.29 Busselton Belmont Substation Substation Bunbury Harbour Bentley Bunbury Cannington Clarence Street Clarence Capel Collier Coolup Kewdale Margaret River Margaret Rivervale Marriott Road Tate Street Tate Picton 66 Victoria Park Pinjarra Welshpool Bunbury Contract Customers Cannington Contract Customers TOTAL LOAD TOTAL TOTAL LOAD TOTAL

2009 Transmission and Distribution Annual Planning Report 143 7.06 7.06 0.78 3.30 3.51 9.46 9.33 2.06 MVA 18.50 13.73 10.97 17.10 36.86 23.08 2013 MW 6.57 6.57 0.65 3.29 3.26 9.42 8.75 1.61 17.39 13.50 10.58 15.40 33.82 21.77 7.06 7.06 0.78 3.30 3.48 9.26 8.10 2.01 MVA 18.50 13.59 10.84 14.06 33.91 22.15 2012 MW 6.57 6.57 0.65 3.29 3.22 9.22 7.59 1.57 17.39 13.37 10.45 12.67 31.10 20.89 7.06 7.06 0.78 5.24 3.30 3.44 9.05 8.02 1.97 MVA 18.50 13.45 10.70 33.06 21.22 2011 MW 6.57 6.57 0.65 4.72 3.29 3.19 9.02 7.52 1.54 17.39 13.23 10.32 30.32 20.02 7.06 7.06 0.78 5.20 3.30 3.41 8.85 7.94 1.93 MVA 18.50 13.31 10.57 32.20 20.30 2010 MW 6.57 6.57 0.65 4.69 3.29 3.16 8.81 7.45 1.51 17.39 13.09 10.19 29.54 19.14 5.89 5.89 0.78 5.17 3.30 3.38 8.64 7.87 1.89 MVA 17.64 13.16 10.43 31.35 19.37 2009 MW 5.50 5.50 0.65 4.65 3.29 3.13 8.61 7.37 1.48 16.58 12.95 10.06 28.76 18.27 TOTAL LOAD TOTAL Yilgarn East Country Contract Customers Wundowie Yerbillon Merredin Mundaring Weir Northam Sawyers Valley Southern Cross Kellerberrin Kondinin Cunderdin Carrabin Substation East Country

2009 Transmission and Distribution Annual Planning Report 144 MVA 41.77 19.13 20.51 64.16 27.18 11.06 11.06 104.98 112.22 120.75 MVA 39.23 28.27 49.27 41.32 158.10 2013 2013 MW 9.00 9.00 90.40 35.71 93.47 17.22 18.46 58.22 24.22 MW 105.23 37.24 27.09 42.14 36.52 142.98 MVA 40.05 18.84 20.11 61.93 26.63 11.06 11.06 101.07 109.35 118.98 MVA 38.26 27.63 48.19 38.63 152.71 2012 2012 MW 9.00 9.00 87.03 34.23 91.08 16.96 18.10 56.19 23.73 MW 103.68 36.31 26.47 41.22 34.10 138.09 MVA 91.93 39.19 18.55 19.70 59.69 26.08 11.06 11.06 103.95 112.73 MVA 37.28 26.99 47.11 37.17 148.55 2011 2011 MW 9.00 9.00 79.16 33.50 86.59 16.70 17.73 98.24 54.17 23.23 MW 35.38 25.86 40.30 32.81 134.34 MVA 88.01 35.18 18.26 19.30 57.46 25.53 11.06 11.06 102.76 110.96 MVA 36.30 26.35 46.04 35.71 144.40 2010 2010 MW 9.00 9.00 75.79 30.07 85.59 16.44 17.37 96.70 52.14 22.74 MW 34.45 25.24 39.37 31.51 130.58 MVA 80.15 36.83 97.73 17.97 18.89 55.23 24.97 11.06 11.06 103.28 MVA 35.33 25.71 44.96 33.68 139.68 2009 2009 MW 9.00 9.00 69.02 31.30 81.40 16.18 17.00 90.00 50.11 22.25 MW 33.53 24.63 38.45 29.70 126.31 Cook Street Forrest Ave Forrest Substation East Perth & CBD Hay Street Joel Terrace 132 kV Joel Terrace Milligan Street North Perth Wellington Street Wellington East Perth Contract Customer TOTAL LOAD TOTAL Eastern Goldfields Substation Black Flag Boulder Piccadilly West Kalgoorlie West TOTAL LOAD TOTAL

2009 Transmission and Distribution Annual Planning Report 145 0.00 MVA MVA 17.85 10.77 63.75 68.19 61.57 65.34 62.91 39.78 37.12 34.42 30.70 56.40 65.93 45.39 130.08 130.08 269.96 2013 2013 MW MW 0.00 16.61 10.00 58.31 63.62 52.62 63.16 58.74 37.79 34.57 31.07 27.63 51.66 58.70 40.85 114.79 114.79 244.47 0.00 MVA MVA 18.93 16.98 60.33 75.69 42.21 36.18 62.24 60.94 32.41 37.26 29.59 54.58 64.05 39.99 130.08 130.08 256.80 2012 2012 MW MW 0.00 15.80 33.70 15.81 29.26 55.18 26.63 70.62 36.07 50.00 60.17 57.01 56.91 35.99 35.39 114.79 232.59 114.79 0.00 MVA MVA 28.00 30.42 24.21 18.93 52.76 16.11 62.16 56.12 34.60 72.48 33.40 59.15 58.98 34.73 232.14 130.08 130.08 2011 2011 MW MW 0.00 26.08 27.45 25.11 48.33 55.33 31.14 15.80 15.00 51.34 67.62 29.30 57.18 55.07 33.00 213.44 114.79 114.79 0.00 0.00 MVA MVA 27.06 28.29 25.85 50.94 60.27 29.20 18.93 51.88 69.26 32.55 55.98 74.01 32.21 221.60 130.08 130.08 2010 2010 MW MW 0.00 0.00 25.20 25.53 23.26 46.66 53.65 26.28 15.80 47.46 64.62 28.55 54.11 68.63 30.60 200.59 114.79 114.79 0.00 0.00 0.00 0.00 MVA MVA 26.12 42.32 49.12 84.80 18.93 47.02 85.94 28.01 33.34 71.08 29.68 202.37 130.08 130.08 2009 2009 MW 0.00 0.00 MW 0.00 0.00 24.33 38.20 45.00 76.32 15.80 43.01 80.43 24.57 32.23 65.92 28.20 183.85 114.79 114.79 British Petroleum (BP) British Petroleum Substation Darlington Substation Baldivis Guildford Kwinana Furnisdale Forrestfield Medina Hazelmere Mandurah Kalamunda Mason Road Meadow Springs Midland Junction Rockingham Munday Waikiki TOTAL LOAD TOTAL Kwinana Contract Customers TOTAL LOAD TOTAL

2009 Transmission and Distribution Annual Planning Report 146 5.69 3.12 9.33 5.52 MVA 61.68 26.00 20.43 15.69 21.22 20.71 19.39 283.34 283.34 2013 MW 5.56 3.08 9.19 5.19 58.38 22.59 18.46 15.34 18.51 19.55 17.89 257.52 257.52 5.64 3.03 8.96 5.43 MVA 59.92 25.68 19.91 15.34 20.79 19.97 18.84 281.51 281.51 2012 MW 5.51 2.99 8.83 5.10 56.72 22.31 17.99 15.00 18.13 18.85 17.38 255.79 255.79 5.58 2.94 8.60 5.33 MVA 49.61 25.35 19.38 15.00 20.35 19.22 18.29 237.64 237.64 2011 MW 5.46 2.90 8.47 5.01 46.95 22.03 17.51 14.66 17.75 18.15 16.87 214.96 214.96 5.53 2.85 8.23 5.24 MVA 46.90 25.03 25.23 14.65 19.92 18.48 17.73 235.81 235.81 2010 MW 5.40 2.81 8.11 4.92 44.39 21.74 22.80 14.32 17.37 17.44 16.36 213.24 213.24 5.48 2.76 7.87 5.14 MVA 44.19 24.70 24.71 14.30 19.48 17.73 17.18 233.98 233.98 2009 MW 5.35 2.72 7.75 4.83 41.82 21.46 22.32 13.98 16.99 16.74 15.85 211.51 211.51 Albany Beenup Muja Bridgetown Substation Collie Katanning Kojonup Mount Barker Manjimup Narrogin Wagin Wagerup Muja Contract Customers TOTAL LOAD TOTAL

2009 Transmission and Distribution Annual Planning Report 147 5.40 5.30 MVA 16.69 19.61 10.20 17.62 21.43 17.72 10.87 27.93 43.52 16.74 25.61 273.91 273.91 2013 5.16 MW 9.66 4.65 16.05 17.65 16.39 18.85 15.45 10.78 26.54 41.05 15.06 22.61 250.26 250.26 5.23 9.67 0.00 5.21 MVA 16.66 16.00 16.22 24.00 10.55 27.25 42.43 16.32 33.78 273.91 273.91 2012 5.00 MW 9.16 0.00 4.57 16.02 14.40 15.10 21.12 10.46 25.89 40.02 14.68 29.99 250.26 250.26 0.00 0.00 9.14 0.00 5.12 MVA 16.63 14.83 23.74 15.11 49.23 41.34 15.91 22.13 263.91 263.91 2011 0.00 MW 0.00 8.66 0.00 4.49 15.99 13.80 20.89 14.98 46.77 38.99 14.31 19.81 241.26 241.26 0.00 0.00 8.61 0.00 5.03 MVA 15.83 13.43 23.47 14.63 47.95 40.24 15.49 20.17 130.58 130.58 2010 0.00 MW 0.00 8.15 0.00 4.41 15.22 12.50 20.65 14.50 45.55 37.96 13.93 18.05 121.26 121.26 0.00 7.85 0.00 8.07 0.00 4.69 MVA 41.69 41.69 12.04 23.20 14.15 46.44 33.00 15.07 18.50 2009 MW 0.00 7.55 0.00 7.65 0.00 4.12 41.26 41.26 11.20 20.42 14.03 44.12 31.13 13.56 16.55 TOTAL LOAD TOTAL North Country Contract Customers Hills Wongan Three Springs Three Rudds Gully Regans Regans Rangeway Oakajee Moora Kalbarri Geraldton Eneabba Durlacher Street North Country Substation Chapman

2009 Transmission and Distribution Annual Planning Report 148 MVA 23.83 23.83 48.49 68.95 90.62 35.79 28.88 94.41 71.37 66.58 51.10 31.52 67.93 72.60 40.23 66.65 39.95 18.42 47.89 76.66 54.49 69.46 57.64 2013 MW 20.50 20.50 45.45 61.81 82.84 33.28 25.96 84.99 63.26 61.27 46.50 28.23 59.09 62.88 36.83 61.97 36.36 16.26 45.59 67.11 51.08 65.17 51.04 MVA 23.83 23.83 43.59 66.68 86.52 17.89 17.04 90.47 64.04 64.13 49.96 29.98 66.21 69.48 46.66 81.53 37.96 17.94 46.36 74.83 52.25 67.16 66.51 2012 MW 20.50 20.50 40.85 59.78 79.09 16.64 15.48 81.44 54.27 59.01 45.47 26.85 57.60 60.17 42.50 75.81 34.55 15.84 44.14 65.51 48.98 63.01 58.89 MVA 23.83 23.83 39.47 64.42 82.42 16.13 16.51 86.54 62.27 61.67 59.88 28.44 64.48 66.35 45.20 79.47 25.57 17.46 27.85 73.01 50.01 79.61 64.07 2011 MW 20.50 20.50 36.99 57.75 75.35 15.00 15.00 77.90 52.77 56.75 54.49 25.48 56.10 57.46 41.17 73.90 23.27 15.42 27.01 63.91 46.88 75.32 56.74 0.00 0.00 MVA 23.83 23.83 35.60 62.16 90.80 82.60 57.22 75.37 58.11 26.90 62.76 54.81 43.74 91.37 24.18 16.98 25.66 71.18 34.76 76.77 61.64 2010 0.00 0.00 MW 20.50 20.50 33.37 55.72 83.01 74.35 48.49 70.08 52.88 24.10 54.60 47.46 39.84 84.96 22.00 15.00 24.89 62.31 33.37 72.63 54.58 0.00 0.00 0.00 0.00 MVA 23.83 23.83 32.49 59.89 98.02 78.66 72.90 72.39 67.31 25.37 61.04 51.68 42.27 87.19 23.47 69.36 33.19 73.32 59.21 2009 0.00 0.00 MW 0.00 0.00 20.50 20.50 30.45 53.69 90.01 70.81 61.78 67.31 61.26 22.72 53.10 44.76 38.51 81.06 22.76 60.72 31.86 69.36 52.43 TOTAL LOAD TOTAL Northern Terminal Contract Northern Terminal Customers Yanchep Yokine Wanneroo Wangara Warwick Padbury Osborne Park North Beach Mullaloo Muchea Morley Malaga Manning Street Landsdale Joondalup Joondanna Henley Brook Hadfields Clarkson Beechboro Northern Terminal Substation Arkana

2009 Transmission and Distribution Annual Planning Report 149 0.00 1.84 MVA MVA 29.98 29.98 18.17 67.78 23.43 62.97 41.89 79.67 46.62 46.95 11.58 34.58 21.28 51.35 74.68 98.87 17.60 69.92 74.77 55.98 317.64 2013 2013 MW MW 0.00 1.62 28.83 28.83 16.35 21.20 59.50 62.60 74.56 36.84 43.92 10.60 41.26 20.00 30.14 68.26 88.57 45.72 65.10 15.09 67.53 49.75 283.02 0.00 0.00 1.83 MVA MVA 29.98 29.98 17.42 22.77 57.84 77.84 65.81 45.79 11.25 41.32 45.43 72.82 95.68 34.04 65.97 50.03 71.18 17.32 53.88 309.66 2012 2012 MW MW 0.00 0.00 1.61 28.83 28.83 15.68 20.60 54.66 72.84 42.84 10.30 60.78 36.34 66.57 85.71 40.21 61.42 29.67 64.28 44.55 14.85 47.87 275.89 0.00 0.00 1.82 MVA MVA 29.98 29.98 16.67 22.10 51.87 76.00 44.63 10.93 63.85 70.96 92.49 39.93 62.01 44.24 67.70 33.49 46.29 17.05 51.77 298.44 2011 2011 MW MW 0.00 0.00 1.61 28.83 28.83 15.00 20.00 49.02 71.13 41.75 10.00 64.87 82.85 58.97 57.74 35.11 61.14 39.15 29.19 41.22 14.62 46.00 265.87 0.00 0.00 0.00 0.00 0.00 1.82 MVA MVA 29.98 29.98 46.43 83.67 32.60 80.19 58.06 61.89 64.43 44.89 43.05 32.95 54.58 16.77 40.05 105.29 295.99 2010 2010 MW MW 0.00 0.00 0.00 0.00 0.00 1.60 28.83 28.83 43.88 79.49 30.96 73.30 94.32 54.06 58.19 57.16 39.45 38.10 28.72 48.62 14.38 35.53 263.56 0.00 0.00 0.00 0.00 0.00 1.81 MVA MVA 29.98 29.98 42.16 81.54 31.77 78.51 54.11 61.71 53.82 43.37 41.86 32.40 52.79 16.49 38.40 101.35 280.94 2009 2009 MW MW 0.00 0.00 0.00 0.00 0.00 1.60 28.83 28.83 39.84 77.46 30.17 71.29 90.79 50.38 55.73 49.71 38.11 37.05 28.24 47.03 14.14 34.07 249.94 TOTAL LOAD TOTAL Southern Terminal Contract Southern Terminal Customers Willeton Thornlie Southern River Riverton Murdoch Maddington Jandakot Gosnells Canning Vale Substation Cockburn Cement Southern Terminal Byford Amherst Substation Australian Paper Mills South Fremantle Bibra Lake Edmund Street Myaree North Fremantle O’Connor O’Connor 132 kV South Fremantle TOTAL LOAD TOTAL

2009 Transmission and Distribution Annual Planning Report 150 0.00 0.00 MVA 48.39 16.26 31.62 33.29 13.16 16.43 18.10 42.31 219.55 2013 MW 0.00 0.00 43.79 14.78 27.35 29.80 11.57 14.50 15.71 37.93 195.44 0.00 0.00 0.00 MVA 46.82 16.04 30.04 32.71 29.14 17.18 41.15 213.09 2012 MW 0.00 0.00 0.00 42.37 14.59 25.99 29.05 25.47 14.92 36.89 189.28 0.00 0.00 0.00 MVA 45.25 15.83 29.49 30.98 28.15 16.27 40.00 205.96 2011 MW 0.00 0.00 0.00 40.95 14.39 25.51 27.52 24.60 14.13 35.86 182.95 0.00 0.00 0.00 MVA 43.67 15.61 22.39 29.25 31.59 21.64 34.46 198.61 2010 MW 0.00 0.00 0.00 39.53 14.20 19.48 25.98 27.74 18.78 30.89 176.59 0.00 0.00 MVA 22.67 20.22 15.39 21.61 27.53 30.52 20.67 33.38 191.99 2009 MW 0.00 0.00 20.61 18.30 14.00 18.80 24.45 26.80 17.94 29.92 170.82 Cottesloe Substation Western Terminal Western Cottesloe 132 kV Parade Herdsman Medical Centre Nedlands Nedlands 132 kV Shenton Park Shenton Park 132 kV University Wembley Downs Wembley Total Load Total

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10 Appendix C – Estimated maximum short circuit levels

This appendix presents tables of maximum faults. This information should be taken as an forecast short circuit levels at each of Western approximate guide only. The short circuit level Power’s South-West Interconnected System calculations were determined using AS 3851- (SWIS) major nodes. 1991: The calculation of short circuit currents in three-phase AC systems. Western Power has prepared these fault levels for three-phase and single-phase to earth

Bunbury Terminal Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Alcoa Pinjarra 132 kV 11.30 11.32 11.65 11.61 Alcoa Pinjarra 330 kV 14.42 13.14 15.69 13.94 Barrack Silicon Smelter 132 kV 8.62 7.95 8.87 8.26 Bunbury Harbour 132 kV 8.15 8.20 8.65 8.66 Busselton 66 kV 3.87 4.98 4.04 5.25 Busselton 132 kV 2.27 2.51 3.65 4.08 Capel 66 kV 4.44 3.99 3.40 2.76 Coolup 66 kV 1.03 0.62 1.03 0.60 Kemerton 132 kV 10.52 11.35 10.81 11.54 Kemerton 330 kV 16.69 16.43 17.72 15.59 Kemerton Power Station 330 kV 15.77 15.36 16.41 14.05 Marriot Road Local 132 kV 9.11 8.99 9.39 9.40 Margaret River 66 kV 1.57 1.34 1.58 1.35 Margaret River 132 kV 0.00 0.00 2.13 2.17 Marriott Rd 132 kV 9.29 9.11 9.59 9.53 Picton 132 kV 9.49 9.93 10.30 10.85 Picton 66 kV 8.01 10.47 8.08 10.56 Pinjarra 132 kV 10.78 9.22 11.56 9.97 Westralian Sands 66 kV 4.27 3.97 3.33 3.04

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Cannington Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Beckenham 132 kV 24.68 27.35 26.13 29.47 Belmont 132 kV 19.49 17.87 19.89 18.58 Bentley 132 kV 16.57 15.15 17.39 16.15 Cannington Terminal 132 kV 26.40 29.25 28.03 31.67 Cannington Terminal 66 kV 12.00 14.58 12.18 14.83 Clarence Street 66 kV 7.42 5.92 7.07 6.63 Collier 66 kV 7.31 5.92 7.12 6.22 Eastern Terminal 330 kV 0.00 0.00 18.41 17.43 Kenwick Link 132 kV 23.82 24.59 25.17 26.11 Kenwick Link 330 kV 14.14 13.41 15.58 14.54 Kewdale 132 kV 18.37 15.77 19.14 16.81 Rivervale 132 kV 17.43 15.03 16.29 15.03 Tate Street 66 kV 10.46 11.34 10.21 10.80 Tomlinson Street 66 kV 8.16 7.13 7.75 6.53 Victoria Park 66 kV 9.94 10.20 0.00 0.00 WEB Forge 66 kV 9.01 8.08 9.24 8.48 Welshpool 132 kV 18.86 18.32 19.81 19.29

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East Country Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Baandee 66 kV 1.71 1.67 1.71 1.67 Bounty 132 kV 0.62 0.74 0.62 0.74 Carrabin 66 kV 0.96 0.76 0.97 0.76 Cunderdin 66 kV 1.63 1.70 1.64 1.69 Kellerberrin 66 kV 1.51 1.69 1.51 1.68 Kondinin 132 kV 1.33 1.60 1.34 1.61 Kondinin 220 kV 2.39 2.38 2.37 2.37 Merredin 66 kV 2.19 2.90 2.20 2.90 Merredin 132 kV 3.27 4.15 3.22 4.10 Merredin Terminal 132 kV 3.44 4.63 3.38 4.56 Merredin Terminal 220 kV 2.37 3.02 2.28 2.91 Mundaring Weir 66 kV 3.46 2.47 3.50 2.50 Northam 132 kV 4.72 5.49 4.88 5.71 Northam 66 kV 4.61 5.78 4.77 6.00 Sawyers Valley 66 kV 3.07 2.27 3.10 2.30 Sawyers Valley 132 kV 0.00 0.00 8.04 6.28 Southern Cross 66 kV 0.53 0.36 0.53 0.37 Wundowie 66 kV 2.70 2.92 2.74 2.96 Yerbillon 66 kV 0.90 0.70 0.91 0.70 Yilgarn 220 kV 2.06 2.01 1.89 1.91

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East Perth & CBD Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Cook St 132kV 20.14 22.47 26.81 31.36 East Perth 66kV 4.98 6.46 5.09 6.58 East Perth 132kV 21.27 23.75 27.59 32.19 Forrest Ave 66kV 4.55 4.98 4.64 5.24 Hay St 132kV 19.16 20.76 23.98 25.93 James St 132kV 16.11 15.84 28.25 32.98 Joel Tce 66kV 4.94 6.40 5.02 6.48 Joel Tce 132kV 20.98 22.70 27.08 30.16 Milligan St 132kV 16.08 16.12 27.45 30.22 North Perth 132kV 18.70 18.25 23.80 23.11 Summers St 132kV 20.95 22.91 27.13 30.78 Wellington St 66kV 4.76 5.52 4.85 5.62 Wellington St 132kV 19.19 20.75 24.06 26.20

Eastern Goldfields Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Black Flag 132 kV 2.69 2.88 2.23 2.51 Boulder 132 kV 5.02 6.41 3.76 4.95 Jan 66 kV 2.08 2.71 2.00 2.62 Jan 132 kV 1.93 2.10 1.79 1.99 Parkeston 132 kV 4.86 5.91 3.71 4.68 Piccadilly 132 kV 4.97 6.38 3.69 4.88 West Kalgoorlie Terminal 132 kV 5.12 6.99 3.68 5.08 West Kalgoorlie Terminal 220 kV 2.73 3.49 2.10 2.75 Western Mining Kambalda 132 kV 2.74 3.07 2.46 2.83 Western Mining Smelter 132 kV 4.31 4.78 3.49 4.06

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Guildford Terminal Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Munday 132 kV 11.63 10.90 12.42 11.81 Darlington 132 kV 11.98 10.87 15.77 15.22 Forrestfield 132 kV 11.63 10.90 12.42 11.81 Guildford Terminal 132 kV 19.85 21.60 21.20 23.35 Guildford Terminal 330 kV 13.52 13.33 16.33 15.69 Hazelmere 132 kV 0.00 0.00 20.62 22.02 Kalamunda 132 kV 10.10 9.16 11.65 10.75 Midland Junction 132 kV 18.26 20.10 19.51 21.68

Kwinana Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Alcoa Kwinana 132 kV 26.50 29.90 33.06 37.59 Australian Fused Materials 132 kV 17.20 15.32 19.28 16.81 BP Refinery 132 kV 21.67 22.66 25.94 26.91 British Petroleum 66 kV 6.51 6.84 5.92 6.44 Broken Hill Kwinana 66 kV 6.58 6.86 5.99 6.46 CSBP 132 kV 20.46 20.06 24.13 23.10 HIsmelt 132 kV 20.28 20.08 23.88 23.15 Kerr McGee Kwinana 132 kV 23.68 25.88 28.66 31.05 Kwinana 66 kV 6.87 7.79 6.22 7.27 Kwinana 132 kV 23.60 26.03 25.78 28.27 Kwinana 330 kV 18.83 20.90 22.34 24.81 Kwinana Desalination Plant 132 kV 23.65 25.76 28.75 31.13 Kwinana Power Partnership 132 kV 22.30 23.75 26.83 28.47 Mandurah 132 kV 8.46 7.87 8.77 8.09 Mason Road 132 kV 23.68 25.88 28.66 31.05 Meadow Springs 132 kV 8.83 8.03 9.13 8.58 Medina 132 kV 17.58 15.46 18.90 16.64 Rockingham 132 kV 16.45 15.10 18.03 16.44 Tiwest Pigment Plant 132 kV 23.68 25.88 28.66 31.05 Waikiki 132 kV 11.71 9.76 12.42 10.81 Western Mining 132 kV 18.74 17.20 21.36 19.14

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Muja Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Albany 132 kV 1.44 1.93 1.77 2.33 Alcoa Boddington 132 kV 8.77 10.08 12.53 13.37 Beenup 132 kV 1.13 1.27 1.13 1.27 Bluewaters Power Station 330 kV 16.22 17.23 23.17 25.71 Boddington 132 kV 8.77 10.08 12.53 13.37 Boddington Reynolds 132 kV 8.77 10.08 12.53 13.37 Bridgetown 132 kV 4.06 4.33 4.11 4.73 Collie 66 kV 2.00 2.44 2.01 2.45 Collie Power Station Terminal 330 kV 15.16 15.69 23.29 25.91 Katanning 66 kV 1.80 1.99 1.80 2.00 Kojonup 66 kV 2.82 3.50 2.83 3.52 Kojonup 132 kV 3.67 3.71 3.71 3.81 Manjimup 132 kV 2.76 2.94 2.78 2.99 Mount Barker 132 kV 1.50 1.64 1.65 1.75 Muja 66 kV 3.43 3.90 3.44 3.91 Muja 132 kV 15.15 18.00 16.09 18.94 Muja 220 kV 7.27 8.60 7.45 8.79 Muja 330 kV 16.95 19.45 20.83 23.22 Narrogin 66 kV 1.79 2.32 1.83 2.37 Narrogin South 66 kV 1.81 2.38 1.85 2.43 Narrogin South 220 kV 3.20 2.60 3.26 2.66 Shotts 330 kV 16.21 17.10 23.81 26.50 Wagerup 132 kV 7.32 5.94 7.39 6.00 Wagerup Terminal 330 kV 12.89 12.44 13.37 12.56 Wagin 66 kV 1.82 1.99 1.86 2.13 Wells Terminal 132 kV 9.99 13.19 15.19 19.47 Wells Terminal 330 kV 5.98 6.25 15.03 14.52 Western Collieries Limited 132 kV 11.81 10.35 12.27 10.59 Worsley 132 kV 11.00 10.87 11.19 10.94

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North Country Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Cataby 132kV 3.89 3.72 4.59 3.89 Chapman 132kV 2.90 3.14 5.60 5.88 Eneabba 132kV 3.57 3.45 13.70 5.34 Geraldton 132kV 3.30 3.84 6.93 7.64 Golden Grove 132kV 0.83 0.54 0.86 0.55 Kerr McGee Cataby 132kV 3.86 3.69 4.55 3.86 Moonyoonooka Terminal 330kV 0.00 0.00 6.14 5.70 Moonyoonooka Terminal 132kV 0.00 0.00 8.97 9.93 Moora 132kV 2.35 2.07 2.37 2.25 Mungarra 132kV 4.84 5.87 7.27 8.32 Rangeway 132kV 2.90 3.18 5.00 5.86 Regans 132kV 3.49 3.53 4.48 4.16 Rudds Gully 132kV 0.00 0.00 5.19 5.84 Three Springs 132kV 3.53 3.14 3.58 3.20 Walkaway Windfarm 132kV 3.98 4.69 6.10 5.87 Wongan Hills 132kV 0.00 0.00 1.02 1.14

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Northern Terminal Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Arkana 132 kV 16.80 17.31 17.85 18.06 Beechboro 132 kV 18.16 17.35 20.10 18.88 Clarkson 132 kV 12.33 11.16 11.92 11.46 Edgewater 132 kV 16.44 15.93 17.26 17.37 Hadfields 132 kV 14.69 13.75 19.23 18.29 Henley Brook 132 kV 11.88 9.38 12.15 9.99 Joondalup 132 kV 0.00 0.00 15.46 15.30 Joondanna 132 kV 0.00 0.00 17.56 17.49 Kerr McGee Muchea 132 kV 12.25 9.38 11.55 9.26 Landsdale 132 kV 16.71 15.99 18.24 17.57 Malaga 132 kV 26.41 33.24 28.90 36.36 Manning St 132 kV 15.49 15.27 16.44 15.95 Morley 132 kV 16.01 16.81 17.88 18.39 Mount Lawley 132 kV 19.14 20.99 20.76 22.44 Muchea 132 kV 15.03 12.59 13.98 12.36 Mullaloo 132 kV 16.44 15.93 17.26 17.37 Neerabup Terminal 132 kV 19.71 21.95 19.06 21.76 Neerabup Terminal 330 kV 9.15 8.27 12.31 12.31 North Beach 132 kV 16.14 16.43 17.20 17.34 Northern Terminal 132 kV 26.49 33.33 29.00 36.46 Northern Terminal 330 kV 13.90 14.40 17.95 18.41 Osborne Park 132 kV 16.81 17.38 17.91 18.36 Padbury 132 kV 14.46 13.43 15.24 14.14 Pinjar 132 kV 23.44 25.74 20.28 22.46 Wangara 132 kV 0.00 0.00 17.58 17.32 Wanneroo 132 kV 17.86 18.61 16.28 17.16 Warwick 132 kV 0.00 0.00 16.85 16.34 Yanchep 132 kV 11.87 10.60 11.54 10.69 Yokine 132 kV 16.89 17.35 18.10 18.47

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South Fremantle Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Amherst 132 kV 17.37 14.89 18.46 16.12 Australian Paper Mills 66 kV 8.80 7.65 6.42 6.60 Bibra Lake 132 kV 18.02 16.45 19.49 17.81 Edmund Street 66 kV 10.14 9.76 7.78 8.18 Myaree 66 kV 8.08 6.62 4.22 4.99 North Fremantle 66 kV 9.42 8.35 7.37 7.20 O’Connor 66 kV 9.22 8.44 3.67 3.69 O’Connor 132 kV 0.00 0.00 17.56 17.79 South Fremantle 66 kV 12.99 16.64 9.31 12.44 South Fremantle 132 kV 24.17 24.28 26.97 28.66

Southern Terminal Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Byford 132 kV 10.89 9.97 11.30 10.31 Canning Vale 132 kV 16.95 16.18 17.64 17.18 Cockburn Cement 132 kV 18.66 16.97 19.73 17.71 Glen Iris 132 kV 22.93 24.81 24.19 26.61 Gosnells 132 kV 20.02 18.99 21.00 20.09 Murdoch 132 kV 21.55 18.88 23.00 20.19 Riverton 132 kV 18.87 15.86 19.93 16.59 Southern River 132 kV 18.16 16.45 19.03 17.44 Southern Terminal 132 kV 29.69 33.98 32.55 37.26 Southern Terminal 330 kV 19.13 20.94 21.93 23.83 Maddington 132 kV 0.00 0.00 21.79 19.66 Willetton 132 kV 0.00 0.00 18.03 17.76

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Western Terminal Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Cottesloe 66 kV 8.60 7.35 8.75 9.15 Cottesloe 132 kV 16.46 13.41 20.97 22.52 Herdsman Parade 66 kV 7.75 5.89 7.88 5.98 Medical Centre 66 kV 9.49 8.75 9.69 9.05 Nedlands 66 kV 10.12 9.79 10.34 10.47 Shenton Park 66 kV 10.51 11.13 10.78 11.44 University 66 kV 9.35 8.40 9.54 8.74 Wembley Downs 66 kV 8.87 7.34 9.03 7.48 Western Terminal 66 kV 12.09 15.39 12.43 16.01 Western Terminal 132 kV 19.79 19.68 22.03 22.07

2009 Transmission and Distribution Annual Planning Report 161

Western Terminal Load Area - 2009 Fault Current (kA) 2014 Fault Current (kA) Fault Levels Three One Three One Substation Phase Phase Phase Phase Cottesloe 66 kV 8.60 7.35 8.75 9.15 Cottesloe 132 kV 16.46 13.41 20.97 22.52 Herdsman Parade 66 kV 7.75 5.89 7.88 5.98 Medical Centre 66 kV 9.49 8.75 9.69 9.05 Nedlands 66 kV 10.12 9.79 10.34 10.47 Shenton Park 66 kV 10.51 11.13 10.78 11.44 University 66 kV 9.35 8.40 9.54 8.74 Wembley Downs 66 kV 8.87 7.34 9.03 7.48 Western Terminal 66 kV 12.09 15.39 12.43 16.01 Western Terminal 132 kV 19.79 19.68 22.03 22.07

2009 Transmission and Distribution Annual Planning Report 363 Wellington Street Perth WA 6000 GPO Box L921 Perth WA 6842 T: (08) 9326 4911 F: (08) 9326 4595 www.westernpower.com.au ELECTRICITY NETWORKS CORPORATION ABN 18 540 492 861