Western Australia's first big battery will now cost an extra $19 million and not be available until after summer, adding further pressure to the state's electricity grid.
More than two years in the making, the Kwinana battery project was announced in October 2020 as a way to strengthen WA's power system, and will be capable of powering 160,000 homes for two hours.
The battery soaks up power from generators or sources like rooftop solar when demand is low but supply is high – like during the middle of the day – and distributes it when the opposite is true.
Celebrating the installation of the first battery units of the project in August, Premier Mark McGowan described it as a "pretty simple and neat solution to the problem we face".
At the time it was hoped the system would be up and running by the end of the year, but that's now been pushed out by at least another two months, beyond what is for some an increasingly nervous summer for the state's power grid.
Minister downplays impact on network
Energy Minister Bill Johnston said he did not expect the delay to significantly impact the ability of West Australians to run their air conditioners and keep the lights on.
"The big battery was never included in this year's summer readiness campaign," he said in a statement.
"There are always challenges in managing WA's unique electricity system.
"Because we are on a separate network, we can't rely on other parts of the country and we are supplying one of the largest grids with a comparatively small population, but it's well prepared for the summer."
A spokesperson for the Australian Energy Market Operator (AEMO), which is responsible for operating the grid that powers more than a million customers from Geraldton to Albany and out to Kalgoorlie, said the delays had been accounted for.
They said combined with coal supply shortages and other issues, AEMO had activated a process not used in WA since 2008, which provides "reserve capacity" on standby, either to generate more power or to cut back demand.
"These reserves will add further resilience to the grid during the challenging summer period when the power system is under increased stress," AEMO's executive general manager for WA, Kate Ryan, said.
Battery 'would certainly help': expert
Associate director at renewable energy consultancy Rennie, Greg Ruthven, said even if the battery was not planned for, there was some hope it could have helped strengthen the grid over coming months.
"The difference between the highest demand day in a mild summer versus the highest demand day in an extreme summer can be 300 or 400 megawatts, so it's a sizeable contribution to that," he said.
"To put it in perspective, the shortfall that [AEMO] identified in meeting the standard for the current summer, for which it's run its tender process, that was also in the order of 150 megawatts. So it would certainly help."
Mr Ruthven said while not necessarily make or break, the battery would have helped widen what was currently a narrowing margin for error, with concerns over the suitability of NSW coal being imported this summer, and a number of the state's biggest gas turbines being offline.
The landmark project was initially costed at $155 million, but last week's mid-year review showed two reasons for the extra $19 million bill.
Treasury papers revealed $7.9 million will have to be spent "resulting from the discovery and rectification of contaminated foundation materials at the battery site".
Testing due to begin in February
However, in a statement a Synergy spokesperson said there was "no contamination of the soil or foundation materials".
"But large amounts of rubble and organic matter were discovered during civil earthworks," the spokesperson said, referring to issues with the site at the decommissioned Kwinana power station.
"Works have been completed to apply suitable soil consistently across the site to level the ground and meet the battery's design requirements."
Synergy will also spend an extra $10.9 million on a "firewall containment system".
"Battery suppliers originally advised that industry standards meant a passive fire design would be adequate for the project," the spokesperson said.
"However, at the beginning of this year Synergy made the decision to install an impermeable firewater containment system to meet emerging understandings of the technology in other jurisdictions."
Those issues as well as supply chain pressures have contributed to delays that mean testing is now not due to begin until February 2023.
"After which the Australian Energy Market Operator will determine when the battery can commence market operations," Synergy said.
"The impacts of global supply chain issues and a tight local resources market have impacted construction projects across Australia."
