Getting the most out of our existing hydropower generation is a key part of our future energy vision. The Tarraleah scheme in the Central Highlands was commissioned in the 1930s and produces around 630 gigawatt hours of energy each year - or 6.5% - of Hydro Tasmania’s total annual production.
We are looking to reimagine the iconic scheme to help meet Tasmania’s future energy needs and better suit a rapidly changing energy market. We conducted a rigorous analysis of five options, carefully considering the social, environmental, commercial, and economic risks and benefits of each option. Our preferred development option has been identified – a full redevelopment (including a new power station) with a pressurised water conveyance. This option delivers the greatest capacity, storage, flexibility and reliability for every dollar invested, while addressing environmental risk.
We recognise that there is significant public interest in the project and renewable energy development in Tasmania generally. The preliminary business case is primarily an internal document to help identify our preferred option and would not normally be published. However, we believe it is important to provide more information and, in that spirit, we are publishing the document in full, with redactions made where information could put us at a commercial disadvantage.
Click on the link below to access our CEO’s covering letter and the preliminary business case. Please note that this preliminary business case was finalised in May 2023 and represents a point in time. As we progress more detailed work, some aspects will change including cost estimates, timeframes and procurement approaches.
>> Tarraleah preliminary business case
Work will now progress on an analysis of the preferred option to develop a full business case ahead of the Final Investment Decision. We will continue to keep the community informed along the way and provide opportunities to talk directly with our team about what is ahead.
We’ve also put together more information on the project.
In March 2021, ARENA and Hydro Tasmania released a knowledge sharing report that presents a framework for making hydropower asset management decisions in a future energy market context, using Tarraleah as a case study. You can access the report here - Repurposing hydropower assets for future market.
ARENA funded Hydro Tasmania’s pre-feasibility study report, looking at how the hydropower scheme might be repurposed for a future energy market. This study recommended a full feasibility study to assess risks and benefits of scheme redevelopment in comparison to progressive refurbishment.
This station is our largest. To maintain environmental flows to the Gordon River, we are currently running an existing large turbine at low load, which is not efficient.
We have investigated a solution to more efficiently generate power from the environmental water flow released to the Gordon River using a smaller turbine designed for these flows.
Our feasibility study demonstrates that the addition of a smaller turbine is both technically and commercially feasible. Implementation of the project would bring a number of benefits including:
The project has been prioritised against other business capital expenditure needs and will not be proceeding to implementation at this stage. However, the future market is changing. Hydro Tasmania will continue to monitor the market for changes that may further improve the value of the project and trigger a review of current capital expenditure priorities.
If you’d like to know more, we’ve prepared a report on the outcomes of the feasibility study which you can download from the link below.
Gordon Power Station Feasibility Study Knowledge Sharing Report
We must invest in our infrastructure for a new era of Tasmanian hydropower that will help meet the state’s energy demands now and in the future. Asset upgrades will be vital to boosting generation and efficiency. In addition to our proposed major construction projects, we continue major refurbishment and upgrade works around the state.
Read more about how we’re investing in our hydropower system here.