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.
Pumped hydro will form a huge part of that. It represents the next generation of Tasmanian hydropower, and lets us re-use our hydro water again and again to create clean energy.
Our studies so far have found huge pumped hydro development potential in the state. Lake Cethana, Lake Rowallan and Tribute have emerged as the most promising pumped hydro sites following studies done over the past 20 months looking at the state’s potential. We've now kicked off our feasibility study, looking in more detail at the potential of each of these sites. If you’d like to know more about the feasibility study and what to expect over the coming months, please have a look through our FAQs below. You can always contact us on pumpedhydro@hydro.com.au if there’s something else you’d like to know.
Our feasibility study is gathering more detailed information and assessing the suitability of each site for future development. This stage will involve engagement and consultation with local communities.
We’ve been out talking to communities in the Mersey-Forth and on the West Coast during August and September, to let locals know more about the study and our investigation areas, how they can be kept informed and consulted, and what to expect in coming months.
Keep an eye on our website for updates on when we will next be out in the community.
In the meantime, if you have a question, you can contact us at pumpedhydro@hydro.com.au
It’s a complex and comprehensive process that we expect will take around 18 months. Important areas that will be looked at include:
It’s expected to take around 18 months to complete feasibility studies, so finishing up around the end of 2020/ start of 2021.
Timing is aligned to the development path of the second interconnector, as the two projects are closely linked. Our timelines may change depending on how the Marinus Link project progresses.
We will start with three pumped hydro project options but we expect to progress only one of those sites to completion of full feasibility. We’ll make that decision later in 2020.
We expect to finalise feasibility in early 2021 and be ready to lodge development approvals for the preferred site.
These pumped hydro projects will require connection to the nearest substation. Upgrades to existing transmission lines will be required and existing easements will be used where possible. Small sections of new transmission easement may be required close to the pumped hydro sites to connect to existing transmission infrastructure.
We’ll do an assessment of transmission requirements for pumped hydro as part of feasibility studies. Impacted landowners will be consulted as part of any new or upgraded transmission line project required for pumped hydro projects that proceed to development stage.
Anyone who lives near the investigation areas is welcome to contact us in the meantime if they have questions or concerns – pumpedhydro@hydro.com.au
We’ve developed a Fact Sheet that explains the geotechnical and geological work that will be happening at Lake Cethana and Lake Rowallan (drilling and test pitting) between September and December.
We are targeting locations at Lake Cethana and Lake Rowallan where some of the major pumped hydro infrastructure might go – the intake from the lake, the water tunnels (also called conveyances), the underground power stations and the new upper water storages.
The sites being investigated are on the western side above Lake Cethana and the western side above Lake Rowallan.
After our samples and data are collected, all holes are filled in and disturbed areas are rehabilitated. This work is done to the standards outlined in our Environmental and Social Impact Assessment.
You can download the Fact Sheet here.
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 and Lake Rowallan options use the existing lake as the lower storage and a new off river upper storage would be constructed.
There are no new water storages for the Tribute option. This option would use existing lakes – Lake Plimsoll and Lake Murchison – and link them.
A part of the pre-feasibility studies was to assess potential sites against environmental criteria. Some of these include; impact to lakes and waterways, threatened species, aquatic ecosystems and conservation areas.
We have aimed to avoid impact to high conservation value areas and to identify sites where environmental impacts are minimal or can be mitigated.
To be successful, pumped hydro has to be environmentally sustainable. Environmental and social impact assessments are a key part of the feasibility phase.
Constructing a new storage will require some land to be cleared. The next phase of assessment will involve identifying the best location, size and design of the new upper storages above Lakes Cethana and Rowallan. Communities will have an opportunity to comment on this work.
Check out our Fact Sheets on each potential development to see the investigation area we’re currently looking at:
The pre-feasibility study assessed potential impacts to existing lakes at the pumped hydro sites. It identified the sites where impacts to the aquatic environment of lakes would be minimal and also where there would be less environmental impact.
There may be some impacts at individual lakes in relation to the storage levels. This will be investigated in more detail during the feasibility studies. We will share this information with communities and give you the opportunity to comment.
Based on our current modelling and studies, we don’t anticipate any significant changes to flows downstream as a result of pumped hydro project operation.
The water would be re-used between the existing lower storage (e.g. Lake Cethana) and a potential new upper storage so it acts like a closed system, having minimal impact on the flow of water down through the schemes in the catchment.
The Mersey Forth scheme is what we call a “run of river” scheme. Downstream flow and operation is mostly driven by rainfall and runoff into the catchment. We don’t expect the existing environmental flow release into the Mersey below Parangana dam to change if pumped hydro was developed.
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 one of these sites, we don’t expect any change to access to the existing lakes. For safety reasons, we anticipate that the new upper storages will need to be closed to public access.
Pumped hydro is a proven technology for storing large-scale clean energy and provides around 96% of total worldwide storage capacity.
The concept of pumped hydro is based on using 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.
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. And that would mean more regional jobs and more 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 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 has released its Initial Feasibility Report considering a second Bass Strait interconnector, Marinus Link, finding it is technically feasible and economically viable. The report found “it would be a strategic interconnection investment providing NEM-wide economic benefits”.
The Federal Government has also announced $56 million to accelerate the delivery of Marinus Link.
You can read more about the initial feasibility assessment and also review the Tasmanian Government’s Current Situation Assessment paper in relation to both Marinus Link and Battery of the Nation.
Building a pumped hydro project would create new jobs in manufacturing, construction and engineering services in Tasmania.
We will be able to more accurately estimate the number of jobs once more detailed investigations are done but as an example, up to 300 people could be employed for construction of one pumped hydro development.
This would be across a range of jobs including design, engineering, project management, civil construction, trades and transport, and support labour.
Trades
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.
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