EnergyAustralia has briefed the Commonwealth Government on the potential for a pumped hydroelectric storage project using seawater to support delivery of reliable, clean energy in South Australia.

EnergyAustralia, together with the Melbourne Energy Institute and the Arup Group, conducted a 12 month investigation into the possibility of developing a pumped hydro project using seawater.

The proposed project would be located in the Spencer Gulf of South Australia and would have the capacity to produce around 100 megawatts of electricity with six-to-eight hours of storage. It could be in operation by the summer of 2020/21.

Fresh water pumped hydro has been used for decades but the proposed project for South Australia would be only the second example of a seawater pumped hydro storage plant anywhere is the world. The first seawater pumped hydro facility, in Okinawa, was a demonstration plant with a maximum output of 30 megawatts. It was decommissioned in 2016.

300 megawatt seawater-based projects are being considered for Lanai, Hawaii, and for northern Chile and a seawater-based project with several reservoirs has been proposed for the west coast of Ireland. Several projects using underground reservoirs of salty water have also been proposed.