The Queensland state government has announced a major upgrade to the state’s biggest pumped hydro generator in yet another boost to energy storage following the dramatic explosion of the Callide C coal generator in late May.

The government’s first response to the Callide C coal explosion and the subsequent loss of power to half a million customers was to announce new battery storage investment as part of a “battery blitz” to boost the grid security that had been exposed by the coal plant failure.

This included news of a 150MW, two hour battery at the Tarong coal fired generator owned by Stanwell, which could be expanded down the track. The state’s first big battery, a 100MW, 150MWh facility at Wandoan South, is due for completion later this year.

The state government soon followed these announcements with news of a $22 million study into a major new pumped hydro project at Borumba Dam.

Now the government, and the state-owned CleanCo, is to invest $14 million to upgrade the Wivenhoe pumped hydro power station, much less at full capacity, but which was called in to operate at maximum output when the Callide incident left a shortfall in the market.

“Never has it been more important to invest in fast ramping, flexible energy generation and storage solutions,” the minister for energy, renewables and hydrogen Mick de Brenni said in a statement.

“When Callide C Power Station went offline in May, we were able to ramp Wivenhoe up to the point it was generating 530 megawatts over a four-hour period, helping to meet demand and stabilise the network.”

The $14 million overhaul will include the repair and refurbishment of one of the 285MW turbines, corrosion protection painting of machinery and pipes, and repairs to a transformer.

“Wivenhoe is the jewel in the crown of Queensland’s publicly-owned energy storage fleet and maintaining it will be critical to achieving our renewable energy target,” de Brenni said.

“That’s why we’ll continue to invest in Wivenhoe and progress plans for pumped hydro at Borumba Dam, with the budget providing $22 million for detailed design and cost analysis of that project.”

Borumba is one of a number of potential new pumped hydro projects under consideration in Queensland, including BE’s Cressbrook project that was shortlisted for federal government funding under its stalled UNGI initiative more than two years ago.

Last month, construction began on the Kidston project located in an old gold mine in north Queensland, the first pumped hydro project to be built in decades in Australia. 

Wivenhoe was rarely used for nearly a decade when it was part of the portfolio of one of the state’s biggest coal generators.

But since it was transferred into the portfolio of the new, renewable energy focused CleanCo in 2019, it has been used more often, particularly as the state experiences more negative pricing events during the daylight hours due to the growing share of rooftop and utility scale solar.

“The recent incident at Callide Power Station highlighted the important role fast ramping and flexible generation assets like Wivenhoe Power Station play in supplying energy reliably for Queensland,” CleanCo CEO Dr Maia Schweizer said.

“We must maintain our generating assets in line with this change in operations to ensure we can continue to meet our mandate to provide reliable, affordable energy for our customers and the Queensland community,” Dr Schweizer said.

The planned overhaul will support up to 100 jobs, the government says. Maintenance works will run from mid-July through until late October 2021.