Coal is retiring, and new sources of renewable energy like wind and solar are becoming more plentiful. As our energy mix changes, we need to maintain the reliability, stability and security of the electricity system. Energy storage is needed to "fill the gaps" and provide a stable, reliable electricity system.
Lake Cethana has been selected as Hydro Tasmania’s preferred site of its top three Tasmanian pumped hydro opportunities and it will now progress to final feasibility.
Deep storage capacity, greater cost certainty, environmental and social sustainability and flexibility in sizing and capacity make Cethana the front runner to finalise feasibility.
Please take a look through our FAQs below and get in touch with our team at pumpedhydro@hydro.com.au if there’s something else you’d like to know.
We will continue to progress our work to align the Cethana pumped hydro opportunity to the second 750MW Marinus Link cable development pathway, which will enable the delivery of additional cost competitive deep storage that the future electricity market will need.
We will get on with the work of finalising our feasibility assessment at Cethana. This will involve more on-the-ground work and local community engagement to look more closely at technical, social and environmental factors.
Community information sessions
Thank you to everyone who attended our community drop-in sessions held in Sheffield, Moina and Lorinna. Our pumped hydro team enjoyed chatting with local residents about the project and sharing more information on our study progress and next steps.
Over the next 6-12 months, we’ll be seeking more community feedback on the project including the pumped hydro development and transmission line options before our plans are finalised.
Keep an eye out for information on when we'll be offering the opportunity to chat with us again.
If the project proceeds, it will require connection to the nearest substation, which is the proposed Staverton Substation. This will follow existing transmission routes as far as possible and is likely to require some sections of new easement and the upgrading of some existing easements.
Landowners who may be impacted will be consulted.
Anyone who lives near the investigation area is welcome to contact us in the meantime if they have questions or concerns – pumpedhydro@hydro.com.au
No, we have excluded the environmentally sensitive Tasmanian Wilderness World Heritage Area (TWWHA) and National Parks from our pumped hydro studies. There will be no pumped hydro sites developed in the TWWHA.
No, we are not investigating new on-river dams as part of any potential pumped hydro project.
Lake Cethana would use the existing lake as the lower storage and a new off river upper storage would be constructed.
Since our studies began, we have aimed to avoid impact to high conservation value areas and we looked to identify sites where environmental impacts are minimal or can be mitigated.
Our models show that the changes in Lake Cethana water levels would remain within the current operating levels but would fluctuate more frequently if a pumped hydro development was constructed.
Feasibility and environmental and social impact assessment (ESIA) studies will investigate the impact of changes in the water level regime in Lake Cethana, in consultation with lake users and the local community.
It’s expected that there would be very little impact on the storages downstream and the water available downstream for irrigation and other downstream users.
Developing more renewable energy on-island will provide more generation flexibility, taking pressure off Tasmanian water resources especially during dry times.
If a pumped hydro development is constructed at Lake Cethana, we don’t expect any change to access to the existing lake. For safety reasons, we anticipate that the new upper storage will need to be closed to public access.
Developing all of this new electricity and storage would mean a bright future for our state. Tasmanians would enjoy some of the lowest power prices in the nation and the comfort of knowing the lights would always stay on. Plus, it would trigger a big growth phase - that means regional jobs and investment for our state.
We do get asked a lot about how all of this will reduce power prices. It’s forecast that the combination of low-cost wind and solar energy backed by flexible hydropower will be the lowest cost form of energy available to consumers in the future. Battery of the Nation is designed to allow Tasmanian customers to access that new low-cost supply mix.
Realising our state’s full renewable energy potential requires more interconnection between Tasmania and Victoria. By having more interconnection, it will open up new investment opportunities for hydropower, pumped hydro, wind and solar development.
We will then produce more than enough energy for our state. With more interconnection, we can export the surplus to support mainland Australia’s transition to renewables.
TasNetworks’ analysis shows that Marinus Link and the associated supporting transmission will support Australia’s transition to a low emissions future by delivering the low cost, reliable, and clean energy that customers expect. The investment will provide additional dispatchable capacity across Bass Strait to support a transforming National Energy Market (NEM).
You can read more about the business case assessment for Marinus Link.
Building a pumped hydro project would create new jobs in manufacturing, construction and engineering services in Tasmania. The number of people you need for construction is driven by the project scale but it is anticipated that up to 300 people could be employed over the construction life of one pumped hydro development.
This would be across a diverse range of skills and roles including design, engineering, project management, civil construction, hospitality services, trades and transport.
It would also support a diverse range of local supply, manufacturing and services including other opportunities like steel fabrication, concrete production, road works, plant hire and accommodation and catering services.
Pumped hydro is a proven technology for storing large-scale clean energy and provides around 96% of total worldwide storage capacity.
Pumped hydro uses excess energy in the system for pumping water back uphill (when the price is very low because there’s too much energy available), and storing energy ready for when demand exceeds supply (and prices are therefore high).
What makes the system efficient is how pumped hydro, wind and solar all work together. Pumped hydro uses surplus energy that would otherwise be wasted. And it can fill the gaps when supply is scarce, maintaining the reliability and stability of our electricity system.
For the technically minded, pumped hydro is typically about 80% efficient, meaning it recovers about 80% of the energy used for pumping when it generates. The loss of energy can generally be attributed to things like friction losses in waterways (tunnels) and when the energy is transmitted.
Check out our short video which shows how pumped hydro works.
We’ve now assessed all 14 options as part of our pre-feasibility studies. The aim was to identify a pipeline of potential future pumped hydro projects that can deliver ~2500MW of capacity and can be developed in stages as the electricity market transitions.
Our pre-feasibility study, jointly funded with the Australian Renewable Energy Agency (ARENA), identified a strong portfolio of cost-competitive future pumped hydro opportunities, with a combined capacity of 3400 MW. That portfolio includes the three most promising sites we’ve already identified.
As well as these promising sites, the pre-feasibility study has identified another three options that form a future pipeline of potential pumped hydro development – at yingina / Great Lake in central Tasmania, Lake Parangana in the state’s North West and between Lakes Margaret and Burbury on the West Coast.
Download the Executive Summary
Download the Summary Report
Views from the Tasmanian community are welcomed and we will continue to keep you informed as studies progress. Send your feedback or questions to pumpedhydro@hydro.com.au or call 1300 360 441.
We welcome views from the Tasmanian community and will continue to keep you informed as studies progress.
We welcome your suggestions on the best way to provide project updates or for you to contact us with questions you may have.
Send your feedback to pumpedhydro@hydro.com.au or call 1300 360 441