EnergyAustralia sells off half share in giant battery designed to help fill gap of ageing coal generator

EnergyAustralia , one of Australia’s three biggest privately owned utilities, has found a financing partner for “the biggest single investment” the company has ever made, the $700 million, four hour Wooreen battery in the Latrobe Valley.

Banpu Energy Australia, the local subsidiary of the Thai energy giant, has bought a 50 per cent share in the 350 MW/1,400 MWh Woreen battery for about $110 million.

The deal provides stable revenue via a long-term offtake agreement with EnergyAustralia, and is seen by Banpu as a way to get into what the company sees as a long term energy trend in Australia. 

“In the transition toward sustainable energy, we believe that BESS (battery energy storage systems) will play a critical role in supporting clean energy infrastructure and serve as a locomotive for Banpu’s Energy Symphonics progress,” said Banpu chief Sinon Vongkusolkit in a statement. 

CLP said in its 2024 full-year results announcement in February that taking advantage of increasing electricity price volatility and replacing its nearby Yallourn coal power plant which closes in 2028 were two priorities behind the big battery. 

Construction started on the project in February and it is due to start operating in 2027, a year before the Yallourn coal power plant is scheduled to close.

It is one of a number of big batteries being built, or planned, to replace or support Australia’s ageing fleet of coal fired generators, with the most notable being at Eraring, Liddell, Collie, Munmorah, Hazelwood, Port Augusta, Stanwell, Tarong, and Kogan Creek.

The Wooreen BESS is next to EnergyAustralia’s Jeeralang gas power plant, south of the town Morwell and east of the shuttered Hazelwood coal pit. 

The closest batteries to the Wooreen BESS are Engie’s 150 MW/150 MWh Hazelwood BESS is just over 3km away to the west; even closer to the north are the two Latrobe battery BESS stages of 100 MW/200 MWh each; and closer again is Ace Power’s massive proposed 620 MW/2,480 MWh installation.

EnergyAustralia will still build and operate the project and handle community engagement, it says.

“Banpu’s international expertise and track record in large-scale energy projects will be invaluable as we work together to deliver Wooreen. This partnership brings together the best of local knowledge and global experience,” EnergyAustralia managing director Mark Collette said in a statement. 

Banpu has been trying to get a toehold in the Australian renewable energy market since it launched a local division in 2020.

Late last year it abandoned attempts to build the 100MW solar element of its Pinecrest project, near Lithgow, to focus only on a 400 MW /800 MWh BESS.

It bought the 87 MW Beryl solar farm between Mudgee and Dubbo in central NSW and the 47 MW Manildra solar farm to the south in 2021.

The company also has two small scale solar projects under 2 MW, a plan to build a pumped hydro system in Lake Macquarie, and a mine waste gas concept for the Mandalong coal mine in NSW.

According to the parent company’s website, it owns 831MW of solar, wind, and “solar rooftop and floating business” projects both in operation and under development, and 3GWh of operational energy storage.