Australia’s biggest privately funded battery under construction at Hazelwood power station site

Australia’s biggest privately funded “big battery” is being built on the site of the former Hazelwood power station in Victoria’s Latrobe valley, Macquarie Group and Engie say.

The 150MW battery will use existing infrastructure at the Hazelwood site to connect to the electricity grid, the companies said in a statement.

Engie shut down Hazelwood, which was Australia’s dirtiest coal-fired power plant, in 2017 and demolished its chimneys using explosives last year.

The battery, which is already under construction at an estimated cost of $150m, is due to be up and running by November 2022.

It will be smaller than the 350MW battery planned for the nearby Yallourn coal-fired power station when it shuts down in mid-2028.

Macquarie and Engie said that in addition to storing electricity during off-peak times and delivering it back into the grid when demand is highest, the battery will help stabilise supply by helping to control the frequency at which it is delivered – something that is expected to become increasingly important as the amount of renewable energy in the system increases.

The battery will be built, operated and maintained by Fluence, a joint venture between German electronics group Siemens and American power generator AES, under a 20-year contract.

It will support the transition to green energy and help “ensure that electricity networks are resilient, reliable and flexible”, Greg Callman, the global head of energy technology at Macquarie’s Green Investment Group, said.

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Engie shuttered Hazelwood with just five months’ notice in 2017 – a scenario that the Victorian government has avoided with Yallourn by arranging with its owner to close the plant, which delivers about 20% of Victoria’s electricity, in 2028, four years earlier than planned.

Before Engie closed it, Hazelwood produced about 25% of Victoria’s electricity and was responsible for about 14% of the state’s emissions.

The nearby open-cut mine from which it sourced brown coal also burned out of control for 45 weeks in 2014 after a bushfire spread into it.

Engie’s chief executive for Australia and New Zealand, Augustin Honorat, said the company had a “longterm commitment” to Hazelwood and the Latrobe valley that included remediating the site and acting as “the builder and owner of a new energy asset that helps with the decarbonisation of the energy system”.