Origin Energy has committed to an investment of approximately $400 million for the construction of a large-scale battery at Mortlake Power Station, Victoria.

The Mortlake Power Station battery is designed to have a capacity of 300MW and is expected to deliver output of up to 650MWh, which Origin said will help to firm variable renewables supply and maintain reliable power for customers.

Origin Chief Executive Officer, Frank Calabria, said, “The Mortlake battery is another significant step in our ambition to lead the energy transition through cleaner energy and customer solutions.

“I am pleased to announce that contracts have been signed with global energy storage systems supplier Fluence and site preparation and civil works are expected to commence over coming months.

“Origin’s strategy is to accelerate renewable energy and storage in our portfolio and we expect large-scale batteries and other storage technologies to play a vital role in Australia’s energy transition. This announcement follows our decision last year to approve Origin’s first large-scale battery at Eraring, which is currently under construction.

“With the proliferation of wind and solar farms, particularly in Victoria’s South West Renewable Energy Zone, the Mortlake battery will help keep the grid stable and support more renewable energy coming into the system as the market continues to decarbonise,” Mr Calabria said.

Mortlake Power Station is the largest gas-fired power station in Victoria with a generation capacity of 566MW. The peaking power station is powered by gas from the Otway Basin.

The battery is expected to be commissioned late in 2026.