A pumped-hydro scheme large enough to generate electricity for 500,000 homes for eight hours would be built on Sydney’s south-western fringe under a proposal by the renewable energy company Zen Energy in a development agreement with WaterNSW.
Pumped hydro, which can cheaply and efficiently provide long-term storage to “firm” renewable energy such as wind and solar is seen as a crucial technology if Australia is to replace its ageing coal-fired power stations before they shut down. The nation’s largest pumped hydro project, Snowy 2.0,due to difficulties in drilling through mud, and protests over the necessity of building long transmission lines through delicate national park.
Water would be pumped from Lake Burragorang into the reservoir during the day when there was abundant solar and wind energy in the grid, and released during periods of peak demand when there was little green power available.The company hopes to complete the 1 gigawatt project by 2030 for under $3 billion. By comparison, the 2.2 gigawatt Snowy 2.0 pumped hydro scheme is now not expected to be completed by 2028 at cost of $12 billion.