Australia’s most powerful battery conducts its first tests as a giant shock absorber for the grid

The most powerful battery operating in Australia – the partially commissioned Waratah Super Battery in New South Wales – has conducted its first tests acting as a kind of giant shock absorber to the grid.

The tests were conducted on Tuesday, when the Waratah battery was asked to both charge and discharge up to its current hold point limit of 360 megawatts for a period of two hours, replicating some of what it will need to deliver to the grid when it completes its commissioning later this year.

At 850 MW, the Waratah battery – built by Akaysha Energy at the site of the shuttered Munmorah coal plant – will be the biggest single unit of any type on Australia’s grid, and at its current allowed capacity of 360 MW it is already the most powerful battery on the grid.

Its two hours of storage will deliver 1680 MWh, and on that scale it will soon be overtaken by a number of four hour batteries, such as the two projects nearing completion in Collie, Western Australia – both more more than 2,000 MWh, and the Eraring battery (2,800 MWh) just a short distance away that is also under construction.

The Waratah battery was contracted by the state government and its energy authorities to deliver up to 700 MW and 1,400 MWh under a so-called System Integrity Protection Scheme, the largest of its type in Australia.

The SIPS contract calls on the battery to act as a giant “shock absorber”, allowing the transmission lines bringing power into the major load centres in Sydney, Newcastle and Wollongong to operate at full capacity. Waratah will intervene if something goes awry.

The Waratah battery has already been operating in the grid within its allowed capacity. It acted as an emergency reserve last November when called on by the market operator, and has since been working through various “hold points” in its commissioning process.

Tuesday’s large charge and discharge – the biggest intervention by any battery so far on an Australian grid – marked the first time the battery had been asked to simulate its shock absorber capabilities. Tests at its full capacity are expected in a few months.

The Waratah battery was built with the specific task of helping fill the gap created by the planned closure of the country’s biggest coal fired power generator at Eraring, but that facility will now stay open until at least August, 2027, after a deal struck by the NSW state government.

The battery has been impacted by construction delays – mostly blamed on the weather – and issues during commissioning, which are not uncommon in Australia and not surprising given the scale and novelty of the project.

The main battery supplier, the US-based Powin, has also filed for bankruptcy protection, one of the first big name casualties of Donald Trump’s random tariff agenda.

However, Powin had already completed installations at the Waratah battery and another smaller Akaysha battery project at Ulinda Park in Queensland, which is now also working through the commissioning process, and Akaysha has since snapped up a number of its staff.