Abstract Due to the onset of climate change, humanity is moving towards using renewable energy technologies as our primary means of generating electricity. With the increased utilisation of renewable energy sources there is a growing need for large scale energy storage capabilities worldwide. When it comes to storing energy in the order of gigawatt-hours, Pumped Hydro Storage (PHS) has been proven to be more effective than any other energy storage method. Despite this, the implementation of new PHS projects is challenging due to the typically high capital cost, long lead times and specific nature of the sites where the technology is applicable. As an alternative to constructing new facilities, the research conducted focused on the viability of performing major upgrades to existing PHS plants as a cost-effective way of effectively increasing the storage capabilities of an electricity grid. This was done by conducting an exploratory case study into a proposed upgrade to an existing Pumped Hydro Storage facility in Queensland. In general, the study into the proposed upgrade yielded promising results both in terms of economic feasibility and environmental impact through the increased utilisation of renewable energy technologies. From this further research into developing and optimising the design proposal was recommended. Furthermore, from the positive results produced it was determined that performing major upgrades on existing PHS facilities can come with various benefits and thus is worth investigating as a cost-effective alternative to constructing new energy storage solutions. i Dedicated to my loving grandad, Gazza. ii Table of Contents 1 Introduction ..................................................................................................................................... 1 1.1 Aim and Research Question .................................................................................................... 1 1.2 Impact ...................................................................................................................................... 1 1.3 Thesis Scope ............................................................................................................................ 1 1.4 Contents of Report .................................................................................................................. 1 2 Background ..................................................................................................................................... 3 2.1 Shift Towards Renewable Energy Technologies .................................................................... 3 2.2 The Problem with Renewable Energy Sources ....................................................................... 3 2.3 Solar PV and the ‘Duck Curve’ ............................................................................................... 3 2.4 Energy Storage as a Solution .................................................................................................. 4 3 Pumped Hydro Storage ................................................................................................................... 5 3.1 Functional Overview ............................................................................................................... 5 3.1.1 Primary Purpose .............................................................................................................. 5 3.1.2 Operating Principle ......................................................................................................... 5 3.1.3 Phases of Operation ......................................................................................................... 5 3.1.4 Major Components and Configuration ............................................................................ 5 3.2 Hydraulic Machinery ............................................................................................................... 6 3.2.1 Turbines ........................................................................................................................... 6 3.2.2 Pumps .............................................................................................................................. 7 3.2.3 Dual Function Pump-Turbines ........................................................................................ 7 3.3 Performance Characteristics .................................................................................................... 7 3.4 Drawbacks ............................................................................................................................... 8 3.5 Potential in Upgrading Existing Facilities ............................................................................... 8 4 Design Framework .......................................................................................................................... 9 4.1 Flow Chart ............................................................................................................................... 9 4.2 Steps Involved ........................................................................................................................10 5 Case Study Method ........................................................................................................................11 5.1 Overview ................................................................................................................................11 5.2 Application .............................................................................................................................11 6 Upgrade Proposal – Wivenhoe Power Station ...............................................................................13 6.1 Selection of Existing Facility .................................................................................................13 6.2 Step 1: Data Acquisition ........................................................................................................13 6.2.1 Facility Data ...................................................................................................................13 6.2.2 QLD Electricity Grid ......................................................................................................13 6.3 Step 2: Viability of Capacity Increase ....................................................................................14 6.4 Step 3: Design Development ..................................................................................................15 7 Evaluation ......................................................................................................................................16 iii 7.1 Overview ................................................................................................................................16 7.2 Cost Analysis..........................................................................................................................16 7.2.1 Capital Cost ....................................................................................................................16 7.2.2 Operational and Maintenance Costs ...............................................................................18 7.3 Expected Return .....................................................................................................................18 7.3.1 Operational Model ..........................................................................................................19 7.3.2 Data ................................................................................................................................19 7.3.3 Method ...........................................................................................................................19 7.3.4 Cost Correction for Effective Changes in Demand ........................................................19 7.3.5 Implementation ...............................................................................................................20 7.3.6 Results ............................................................................................................................20 7.4 Environmental Impact ............................................................................................................20 7.4.1 Expected Emissions if Operational in 2017 ...................................................................21 7.4.2 Future Emissions Prediction and Offset Potential ..........................................................21 8 Sensitivity Analysis ........................................................................................................................23 8.1 Overview ................................................................................................................................23 8.2 CAPEX Sensitivity .................................................................................................................23 8.3 Annual Return Sensitivity ......................................................................................................25 9 Discussion of Results .....................................................................................................................27 9.1 CAPEX Predication ................................................................................................................27 9.2 OPEX Prediction ....................................................................................................................27 9.3 Expected Return .....................................................................................................................27