Coal is retiring, and new sources of renewable energy like wind and solar are low cost and becoming more plentiful. But they are variable so energy storage is needed to help fill the gaps and maintain the reliability and stability of our electricity supply. That’s where Tasmania can help!
We’ve been assessing Tasmania’s pumped hydro development opportunities around the state.
In August 2019, we announced the start of a feasibility assessment of pumped hydro development opportunities at Lake Cethana and Lake Rowallan in the North-West and near Tribute Power Station on the West Coast.
These sites were identified as the three top priority pumped hydro opportunities from a $2 million pre-feasibility study jointly funded by the Australian Renewable Energy Agency (ARENA) and Hydro Tasmania.
We have been gathering more detailed information through our feasibility study and assessing the suitability of each site for development. These opportunities were assessed on a range of technical, environmental, social and economic factors.
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 and technical certainty, environmental and social sustainability and flexibility in sizing and capacity make Cethana the preferred to finalise feasibility. 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.
Selecting a suitable pumped hydro site for future development is a complex process! There are many different factors that we need to look at and prioritise. Our “multi-criteria analysis” uses technical, environmental, social and economic factors to make the assessment including:
Further analysis of the future electricity market has demonstrated the value of deep storage. Deep storages have a duration of 12+ hours. Market modelling shows this is the sort of long duration storage the future electricity market will require as the penetration of wind and solar continues to increase.
We’ve selected to a project footprint that has the flexibility to optimise for longer storage durations (essentially ‘future proofing’ the opportunity).
Early feasibility work has shown that the initial design option of 600MW and 11 hours can be scaled up to 750MW (to take full advantage of the increased sizing of the Marinus Link interconnector) and up to 20 hours deep storage duration (to meet expected future market needs).
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.
Community information sessions
As wind and solar power continues to grow, water can play an important role in bringing renewable resources onto the power grid. One way is by storing energy through a proven technology known as pumped hydro energy storage.
Pumped hydro is a flexible technology that can respond to various electricity demands. It consists of reservoir at higher elevation (upper storage) and a reservoir at lower elevation (lower storage). When the demand for electricity is low, or when renewable sources are abundant, water is pumped to the upper storage. It is then stored.
When the demand for electricity is high, or when renewable sources are scarce, the water in the upper storage is used to generate electricity.
Pumped hydro helps to ensure electricity network reliability and enables the addition of more renewable electricity to the grid, resulting in a lower cost of electricity generation.
Our short video explains how it all works!
Australia gets most of its power currently from coal-fired power stations but these stations are starting to close and this will continue over the next few decades.
Wind and solar are now starting to replace coal-fired generation but they are variable. That’s simply because the sun doesn’t always shine and the wind doesn’t always blow.
So we’ll need energy storage in the future, to provide back-up (fill the gaps) and ensure energy is reliably available when consumers need it.
Pumped hydro is a proven technology for storing large-scale clean energy and makes up around 95% of grid energy storage globally.
Pumped hydro technology:
Why here is Tasmania? Our state has natural advantages in developing pumped hydro because we have existing assets and storages, and very suitable topography with lots of steep hills.
Want to find out more? Check out this short video.
We’ve put together some commonly asked questions about pumped hydro.
We welcome views from the Tasmanian community and will continue to keep you informed as studies progress. Your suggestions on the best way to provide project updates are welcomed and if you have questions, please contact us.