A switch has been flicked on Australia’s largest privately funded utility-scale battery at the site of a retired coal power plant in Victoria’s east.

The Hazelwood battery storage system was opened by Victorian Energy Minister Lily D’Ambrosio in a ceremony at the former Latrobe Valley power station site on Wednesday.

The battery, which is expected to have a lifespan of 20 years, has been built next to the former brown coal generator after it was decommissioned in early 2017 with little notice.

It can store 150 megawatts of power, the equivalent of an hour of energy generation from the rooftop solar systems of 30,000 Victorian homes.

The project has been jointly funded and developed by French energy giant Engie and newly formed big battery subsidiary Eku Energy.

It was built by global company Fluence.

Three coal-fired power plants remain in operation in Victoria. They are expected to close in coming years as the state pursues its energy storage and emission reduction targets.

Ms D’Ambrosio said the new battery would complement Geelong’s 300MW battery and has the capacity to power about 75,000 homes for one hour during the evening peak.

“This battery marks an important step forward in the transformation of this historic site from a former coal-fired power station to an active participant in Victoria’s renewable energy system future,” she told a crowd of assembled guests.

“The Latrobe Valley will continue to play an integral part in the energy mix for our state.”

Engie Australia and New Zealand chief executive Rik De Buyserie said the wider context of the storage system’s location could not be ignored.

“Strategically and commercially this is the perfect site for better access to the transmission yard and its unused capacity makes the location ideal,” he said.

– AAP