Storage

State owned utility’s newly opened grid battery has been “re-rated” to be the biggest in Australia

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The state owned utility Synergy has formally opened its third big battery project – all completed in the last three years – and it turns out to be the biggest in the country in terms of storage capacity.

The Collie battery has previously been described by its owners as a 500 megawatt (MW), 2,000 megawatt hour (MWh) facility, which would put it at number 2 in the country so far, behind the 560 MW, 2,240 MWh Collie battery that is owned and operated by Neoen and located just up the road.

But in media releases published by the state government and Synergy on Sunday, after its official opening, the battery is now described as having 2,400 MWh of storage, which would put it as the biggest in the country, at least until the massive batteries at Eraring in NSW and Supernode in Queensland are complete.

“The 500-megawatt (MW) Collie Battery Energy Storage System (CBESS) has 2400 megawatt hours (MWh) of energy storage – enough to power about 785,000 homes for more than four hours   – and is one of the biggest batteries in Australia.,” the company said in a statement.

Well, actually, the biggest.

A company spokesperson confirmed to Renew Economy that the size of the battery has been “re-rated” after completion of the project.

The Collie battery is one of around a dozen that are being built in the state as it rushes to build enough capacity to allow for the closure of its remaining coal fired generators by the end of the decade. The battery is built in the shadow of one of those coal generators, the 300 MW Collie facility, which is scheduled to shut down next year.

“Not only is the town now home to Australia’s biggest batteries, but its future has also been bolstered by our updated Just Transition Plan, which will provide further certainty to the local workforce,” state premier Roger Cook said in a statement.

“I want to keep WA’s economy the strongest in the nation by securing the State’s next generation of job-creating projects.”

State energy and decarbonisation minister Amber-Jade Sanderson said the Synergy Collie battery will capture wind and solar generation and store it for use it to power homes when needed.

“Renewable generation and storage backed by gas is the least-cost energy mix for households and businesses and will put downward pressure on prices as we exit State-owned coal fired power by 2030,” she said.

The local MLA, Jodie Hanns added that the existence of the two biggest operational batteries in Australia will ensure the town continues its significant role in powering WA’s main electricity system.

See Renew Economy’s Big Battery Storage Map of Australia for more information.

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Giles Parkinson is founder and editor-in-chief of Renew Economy, and founder and editor of its EV-focused sister site The Driven. He is the co-host of the weekly Energy Insiders Podcast. Giles has been a journalist for more than 40 years and is a former deputy editor of the Australian Financial Review. You can find him on LinkedIn and on Twitter.

Giles Parkinson

Giles Parkinson is founder and editor-in-chief of Renew Economy, and founder and editor of its EV-focused sister site The Driven. He is the co-host of the weekly Energy Insiders Podcast. Giles has been a journalist for more than 40 years and is a former deputy editor of the Australian Financial Review. You can find him on LinkedIn and on Twitter.

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