Proposed to be built in Cultana in Spencer Gulf in the state of South Australia, the hydro power project is expected to cost A$477m ($373m).

The seawater pumped hydro energy storage (PHES) facility has been found to be technically feasible at an optimal capacity of 225MW to go along with storage capacity of 1,770MWh.

According to ARENA, the facility will have eight hours of storage which is identical to the storage of over 126,000 home batteries.

A statement from Australia Prime Minister Malcolm Turbnull read: “The report is encouraging for further work on saltwater pumped hydro.

“The study shows that the Cultana project is technically feasible, can address the market need for energy firming to facilitate the growth of renewable energy in South Australia and is economically viable under a range of plausible scenarios.”

The feasibility study was carried out by Energy Australia in partnership with Melbourne Energy Institute and Arup.

ARENA CEO Ivor Frischknecht said: “Pumped hydro is the most established and common form of grid-scale storage which can capture and harness electricity produced by solar and wind so it is available when needed.

“We are exploring the potential for pumped hydro across Australia, and the findings of this study are promising for a seawater plant at Cultana.”

Subject to further engineering design, economical modeling and planning approvals, the project is anticipated to become operational by 2023.

In a PHES project, water is pumped uphill to a storage reservoir with a turbine releasing it to deliver surplus energy into the power grid when required.

Pumped hydro storage systems owing to the rapid rate of dispatch are considered to be a reliable source of energy for balancing peak demands and acting as backup for renewable electricity production.


Image: A feasibility study for the Cultana seawater pumped hydro plant yielded promising results. Photo: courtesy of Australian Renewable Energy Agency.