Origin presses go on Eraring battery to help replace Australia’s biggest coal plant

Origin Energy has decided to press go on the first stage of the Eraring battery, part of a suite of investments that will help replace the capacity to be lost when the Eraring coal generator, the biggest in the country, closes down.

Origin says it has chosen Finnish group Wärtsilä to build the first stage of the $A490 million battery, which will be sized at 460MW with two hours of storage (920MWh) – which would be the biggest in Australia if built now.

But it is likely to be dwarfed by the so-called Waratah “super” battery, which at 850MW/1680MWh is also destined to help replace the lost coal output and will be completed around the same time.

Work on the Eraring battery will start within weeks, and it is scheduled to come online in the last quarter of 2025, shortly after the current timeline for the closure of the last Eraring coal units (August, 2025), although the exact closure timing is not locked in.

The Eraring battery could grow to 700MW and up to four hours of storage (2,800MWh) depending on the evolution of the market. That would make it the biggest battery in the country’s main grid.

The choice of Wärtsilä is interesting. It is currently commissioning the 250MW/250MWh Torrens Island battery in South Australia, another installation destined to replace ageing fossil fuel generation.

There is now intense competition among battery providers, with Tesla, Doosan, and Fluence also winning key contracts in the past year.

Håkan Agnevall, the president and CEO of Wärtsilä, said it was the biggest battery contract to date for the company.

“With significant solar and wind resources, Australia is in a unique position to rapidly decarbonise its energy sector. Flexible capacity, provided by energy storage projects like Origin’s Eraring battery or grid balancing engines, will be vital to achieving that as the share of renewables increases,” he said.

“The scale of this project positions Wärtsilä at the heart of that trend, delivering gigawatt-scale energy storage projects in each of our key markets around the world.”

Origin CEO Frank Calabria said approval of the Eraring battery is an important milestone for Origin and another significant step in its strategy to lead the energy transition and accelerate renewable energy and storage.

“We are pleased to make this significant capital investment in Origin’s first major battery project to support the growth in renewable energy that’s occurring across the NEM, together with the expansion of our own portfolio of renewable energy developments,” he said in a statement.

There was no immediate word on the state of negotiations with the new NSW Labor government, which has expressed its frustration at what it sees as the “early” closure of Eraring, and has even raised the possibility of buying the generator to keep it running for many years.

That would likely have a disastrous impact on renewable and storage investment if it did happen, although many in the market suggest one or two units could be kept open – under current ownership – if there is insufficient replacement capacity  by that time.

The announcement comes as the Liddell coal generator, the oldest in the country, is scheduled to start closing the last three units in coming days, with the final curtain to be drawn on Friday, April 28.

Much has been made of warnings of energy shortfalls and “major blackouts”, by the Australian Energy Market Operator, but its modelling has simply been based on what it sees as “confirmed” projects, which have not included Eraring battery or the new generation and storage to be built under the NSW renewable roadmap.

Results of the first of multiple auctions are expected to be released soon, and a second auction for at least 380MW of new firming capacity, likely to be a big battery or demand response, is also underway.

Origin is also investing in its own renewable capacity, including through long term contracts, while its likely new owner Brookfield Asset Management, has made it clear it will spend $20 billion building 12GW of new wind, solar and storage by 2030.

Origin’s head of energy supply and operations, Greg Jarvis said Eraring is a strategic site with high quality connection infrastructure that enables the company to deliver energy into major demand centres.

“Development of the Eraring battery is a key next step as we look to transform the Eraring site for the future, given our intention to exit coal-fired generation by as early as August 2025.”

“We are grateful for the strong support Origin has received from the local community and other stakeholders, and we look forward to working with our key contractors to deliver the Eraring battery safely and expeditiously, consistent with the conditions of approval granted by the NSW Government,” Jarvis said.

The Eraring battery project received initial planning approval from the NSW Department of Planning and Environment in May 2022. Wärtsilä will be supported by Enerven, a subsidiary of SA Power Networks, which will provide design and construction services.

See RenewEconomy’s Big Battery Storage Map of Australia