1 in the MATTER of the Resource Management Act 1991 and in THE
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1 IN THE MATTER of the Resource Management Act 1991 AND IN THE MATTER of a submission and further submissions by TrustPower Limited on the Proposed Canterbury Land and Water Regional Plan STATEMENT OF EVIDENCE OF PETER BRYAN LILLEY ON BEHALF OF TRUSTPOWER LIMITED 1 INTRODUCTION 1.1 My full name is Peter Bryan Lilley. 1.2 I am TrustPower Limited's ("TrustPower") Engineering Manager, a position that is responsible for, amongst other things, the optimisation and enhancement of TrustPower's hydro-electric generation and irrigation assets and the development of new schemes. Prior to this position, I was employed as the Hydro-Development Manager and was responsible for the hydraulic and safety performance of the various dams and structures within TrustPower's hydro-electric generation portfolio. 1.3 I am also currently TrustPower's Acting Environmental Manager. In this position, I am responsible for TrustPower's environmental portfolio, which sees me managing TrustPower's interest in resource consent applications, district and regional plans/policy statements, legislation, Treaty of Waitangi matters, environmental compliance and hazardous substance programmes. 1.4 I hold the qualification of Bachelor of Engineering (Civil) from the University of Auckland (1989) specialising in the areas of catchment hydrology, river hydraulics and water resource engineering. I am a member of the New Zealand Geotechnical Society, the International Society of Rock Mechanics, and the New Zealand Society of Large Dams on which I am the current vice 2510798 FINAL 2 chairman. I am also on the ICOLD Committee (International Commission on Large Dams) on Public Safety around Dams. 1.5 Prior to joining TrustPower in June 2000, I was an Associate of Riley Consultants Limited, a firm comprising specialist Water Resources and Geotechnical engineering consultants. My experience over this time consisted of safety evaluations of dam and associated structures, hydrological analysis and scheme optimisation and enhancement investigations. 1.6 Within the Canterbury region, over the past 10 years I have been involved in a range of irrigation and generation enhancement options including development of the Highbank Pump Station (completed in 2010) which supplies water to Barrhill Chertsey Irrigation Limited ("BCI"). I also have an active role in providing strategic and technical assistance to ongoing workstreams being undertaken within the framework of the Canterbury Water Management Strategy ("CWMS"). 2 SCOPE OF EVIDENCE 2.1 This statement of evidence address the following matters: (a) Overview of TrustPower's electricity generation operations. (b) TrustPower's interest in Canterbury Region. (c) Specific overview of the Lake Coleridge Project. (d) TrustPower's interest in, and submission on, the Proposed Canterbury Land and Water Regional Plan ("Proposed Plan"). 3 OVERVIEW OF TRUSTPOWER 3.1 TrustPower is a home grown, privately owned, company which is a predominantly New Zealand owned (more than 90% of its shares are owned by the Tauranga Energy Consumer Trust and Infratil). TrustPower has its origins in the Tauranga Electric Power Board, which was established in 1924. TrustPower was formed pursuant to the Energy Companies Act 1992, as part of the deregulation of the electricity supply industry. 3.2 Until 1999, TrustPower was a vertically integrated company (that is, it had generation, local transmission, and retail interests) with a regional focus. 2510798 FINAL 3 3.3 Following the 1999 electricity industry reforms (introduced by the Electricity Industry Reform Act 1998), TrustPower sold its local transmission business and grew its generation and retail operations. In this respect, TrustPower's customer base has grown from 50,000 to 220,000, while its annual generation output has increased from approximately 300 GWh to 2,500 GWh. Today, TrustPower is the nation's fifth largest retailer and fifth largest generator. Generation Philosophy and Current Generation Portfolio 3.4 Three key features of TrustPower's generation philosophy and portfolio distinguish it from New Zealand's other large generators: (a) a commitment to small to medium hydro generation and wind generation; (b) a commitment to local supply; and (c) a commitment to the use of renewable resources. 3.5 Nationally, TrustPower now owns and operates a portfolio of 36 hydro-electric power stations and two wind farms. These facilities occupy substantial areas of land, a number of which are both located and effectively managed within environmentally sensitive areas, including within National Parks. 3.6 All generation schemes have two primary descriptive factors. The first is the installed capacity of the scheme which is expressed in MW (megawatts) and is the maximum amount of energy that the scheme can produce at any given time. The second factor is the output of the scheme, expressed in MWh or GWh (megawatt hours or gigawatt hours). This is a measure of the total amount of energy that the scheme produces in a given period, usually a year. 3.7 In terms of scale, TrustPower's hydro schemes vary from 0.43 MW / 3.7 5GWh at Kaniere Forks (enough to supply the electricity needs of about 470 homes) to 101 MW / 215 GWh at the Waipori Scheme (about 27,000 homes), and are distributed throughout New Zealand. Appendix 1 contains a figure which highlights the location of the company's generation assets. The table in Appendix 2 summarises the key attributes of TrustPower's generation assets. 2510798 FINAL 4 3.8 Overall, I believe TrustPower's emphasis on moderate, renewable and local generation places TrustPower squarely in line with the sustainable management purpose of the Resource Management Act 1991 ("RMA"). 4 TRUSTPOWER'S INTEREST IN THE CANTERBURY REGION 4.1 Within the Canterbury Region, TrustPower owns and operates the Coleridge Hydro-Electric Power Scheme ("Coleridge HEPS"), and the Montalto and Highbank Power Stations. The location of these schemes is marked on the map attached as Appendix 3 to this evidence. 4.2 Cumulatively, these three power stations have an installed generation capacity of approximately 69 MW and generate approximately 355 GWh per year. This is equivalent to providing sufficient electricity to power approximately 44,000 households. The Coleridge HEPS 4.3 The Coleridge HEPS officially commenced operation in 1914. The Coleridge HEPS is owned and operated by TrustPower and has an annual energy production capacity of approximately 260 GWh per year. 4.4 The Coleridge HEPS is situated between Lake Coleridge and the Rakaia River (Appendix 3). It utilises natural lake storage, augmented by canals containing diverted inflows from the Harper and Wilberforce Rivers (at the western end of the lake catchment) and the Acheron River via Coleridge Stream (at the eastern end of the catchment). Water from the lake travels down two intake tunnels on the south-eastern shore of the lake to the Coleridge HEPS, located adjacent to the Rakaia River. 4.5 A 3 m high constructed dam and gate across Lake Stream at the northern- western end of the lake is used (in combination with the HEPS intakes) to control the operating levels for the lake between 505.6 m and 509.4 m above mean sea level. The control gate on Lake Stream, which when open allows lake outflow via Lake Stream, is only permitted to open if required due to circumstances beyond the control of the consent holder. In normal operating conditions, the diversions are managed to ensure that all water is discharged via the intake and tunnels to the Coleridge HEPS. 2510798 FINAL 5 4.6 During normal operation of the Coleridge HEPS, approximately 26 m3/s on average is drawn from Lake Coleridge. TrustPower is permitted to divert up to 40.1 m3/s of water from Lake Coleridge into the Coleridge HEPS. Water diverted from the lake is fed directly to the Coleridge HEPS and its five generating turbines. The tailrace below the Coleridge HEPS enables water to be discharged into a side braid of the Rakaia River. 4.7 The station is operated in response to demand for energy and inflows to the lake. During the autumn and winter when inflows are typically lower, additional water is supplied out of storage to meet energy demand resulting in the lake level being lowered over its operating range. During the spring and summer, in response to higher inflows and lower energy demand, the lake level will typically rise or be maintained at higher levels. 4.8 In addition to the HEPS, the lake supplies water to the local Coleridge Village via the existing intake and tunnels. The Montalto / Highbank Power Stations and the Rangitata Diversion Race 4.9 TrustPower owns and operates the Montalto Hydro-Electric Power Scheme ("Montalto HEPS") and the Highbank Hydro-Electric Power Scheme ("Highbank HEPS") which are located on the Rangitata Diversion Race ("RDR"). The RDR is a 67 km long race system that provides water for the irrigation of 66,000 hectares of land between the Rangitata and Rakaia Rivers. Three irrigation distribution schemes connect to the RDR (Mayfield Hinds, Valetta and Ashburton Lyndhurst). 4.10 The Montalto HEPS is located on the RDR, approximately 16 km from the intake on the Rangitata River. The Montalto HEPS was commissioned in 1982 and utilises the natural fall in the RDR for the generation of electricity. The station has an installed capacity of 1.9 MW. 4.11 The Highbank HEPS is located at the terminus of the RDR. Outflows from the Highbank HEPS represent the only major inflow to the Rakaia River below the Rakaia Gorge, and the RDR is strategically important infrastructure for irrigation development on the Canterbury Plains (south of the Rakaia River). The Highbank HEPS utilises water not required for irrigation or stockwater to generate hydro-electricity. 2510798 FINAL 6 4.12 The Highbank HEPS currently has an installed capacity of 28 MW and generates between 75 and 130 GWh of electricity per annum.