Not many people know that Shoalhaven, one of Australia’s largest pumped hydro power systems located in NSW’s scenic Southern Highlands region, has been quietly supplying electricity to NSW households and businesses for more than 40 years. And now Origin is set to expand it and supply more reliable and affordable energy to customers, as well as supporting the shift to renewables.
Pump hydro is like a giant battery. Water is pumped uphill to a dam or reservoir when electricity is cheap and plentiful, where it is stored before being released to generate electricity when it is needed most. It can dispatch energy to the grid faster than any of our other gas or coal-fired plants, with Shoalhaven able to feed into the grid in just three minutes.
At the moment, water is typically pumped uphill at night when largely coal-fired electricity is cheap, but things are changing.
With more large scale solar and wind projects entering the market, we expect that in just a few years’ time when many more solar and wind projects will be online, we will be using renewable solar and wind energy to pump water uphill to store during the day, and letting it go in the evening peak when you go home to cook dinner and watch TV.
One of the current limitations of renewable energy is its intermittency – when the sun isn’t shining or the wind is not blowing they’re unable to generate electricity. Pump storage hydro can help smooth out this intermittency by pumping water uphill at low cost on sunny days, then dispatching water for generation at times when there is no sun or wind. It’s also the perfect complement to renewables because pumped hydroelectricity can be dispatched to the grid in a matter of minutes and react to sudden changes in supply, particularly wind generation.
Ready to go
Origin is responding to the changes occurring in the Australian electricity market.
When Shoalhaven was first designed in the late 1960s, a much larger pump hydro generating plant was envisaged. During construction in the 1970s, space was set aside for additional generation units and pipelines, transmission lines and dams are already in place. This means an expanded Shoalhaven can be delivered quickly and cost effectively with less community or environmental impacts.
Now, with the support of the Australian Renewable Energy Agency (ARENA) Origin will begin work on a $5 million feasibility assessment of plans to nearly double the plant’s overall generating capacity via a new 235MW generating unit housed in an underground power cavern, which will minimise surface and visual impact.
ARENA is contributing $2 million towards the detailed feasibility assessment that will include technical and environmental studies as well as regulatory approvals. The feasibility study will also provide insights that for other hydro energy projects.
The expansion of the scheme would play a key role in helping us transition to a lower carbon future and potentially power an additional 80,000 homes.