Major utility AGL Energy has announced a big expansion of its big battery plans, with a 15-year deal for a new 100MW/150MWh “giant” battery to be built next to the planned Wandoan solar farm in Queensland which could grow to 1,000MW, the biggest in the country.

The new battery – first flagged nearly a year ago – will also be one of the biggest grid-scale batteries in Australia, although it will be pipped in size by the expanded Tesla big battery at Hornsdale in South Australia, which is growing from 100MW/129MWh to 150MW/194MWh, and possibly by some other battery projects planned for that state at Port Augusta and Solar River.

It may yet become the biggest because the project developer, Vena Energy, still harbours plans to build up top 1000MW of solar PV at Wandoan and up to 450MW of storage capacity, to be developed across several stages.

AGL had submitted the idea for a Queensland big battery to the federal government’s controversial Underwriting New Generation Investment scheme. But neither it, nor any other battery projects made the shortlist of 12, and recently energy minister Angus Taylor announced that a peaking gas generator was one of the first two projects chosen to receive government support.

Many in the industry, however, expect that battery storage represents a smarter, cleaner and cheaper alternative in many instances that peaking gas generators, and it is telling that the Coalition chose to provide funding for a long existing technology, rather than encourage new ones.

AGL, even though it has built new fast-start gas generators in South Australia – largely to partially replace its ageing gas fleet in that state – has already hailed the “dawn of the battery age”.

Late last year AGL announced a deal for 200MW/400MWh of battery storage in NSW, starting off with a 50MW/100MWh battery to be built by Maoneng next to the 200MW Sunraysia solar farm currently queuing for connection in – NSW.

AGL also operates the smaller 30MW/8MWh Dalrymple North battery in South Australia, located next to the Wattle Point wind farm that it owns and operates, and the Wandoan battery will provide “firm capacity” to support the huge 453MW Cooper’s Gap wind farm in Queensland which is nearing completion.

AGL will have full operational dispatch rights over the Wandoan battery, but the facility will be built, owned and maintained by Singapore-Based Vena Energy, a company that already operates the Tailem Bend solar farm in South Australia and has projects in the pipeline in three different states and operating projects elsewhere in Asia.

AGL CEO Brett Redman last year hailed the “dawn of the battery era” when announcing the Maoneng deal, and repeated the dawn analogy on Wednesday, telling reporters that Australia was “staring at the dawn of battery age,” and adding that it would be pivotal to providing firming capacity in transformation from coal to renewables.

“The BESS will enable AGL to leverage excess solar generation in Queensland and provide capacity when the Coopers Gap Wind Farm and other renewable power sources are not generating,” Redman said in an earlier statement.

The company is also investigating several pumped hydro storage options, including at Kanmantoo in South Australia and Bells Mountain in NSW, and a 50MW battery at Broken Hill. It is also looking at a gas firming power station in Newcastle.

“More broadly we have $1.9 billion of energy supply projects completed or in construction and another $2 billion in the pipeline, subject to feasibility and stable policy settings, which will all help to put downward pressure on prices for customers.”

Ven Energy, formerly known as Equis Energy, has long held plans to build up to 1,000MW of solar PV around Wandoan, with the possible addition of battery storage). It expects to complete the battery within 18 months, and then have the first stage of the $650 million Wandoan South solar project in place by 2021 that could still expand to 1,000MW of solar and 450MW of storage.

“The BESS (battery energy storage system) is a major milestone in the continuing modernisation of Queensland’s energy supply and improves the reliability of the power grid,” said Vena Energy CEO Nitin Apte.

“The project will bolster a positive investment environment for future projects, as well as encourage broader adoption of renewable energy in Queensland and in Australia.”

Queensland energy minister Dr Anthony Lynham said the decision to build the battery showed that “Queensland’s renewable energy revolution is steaming ahead and the next wave is battery storage.”

He also took a pot-shot at “climate deniers” (and presumably the Coalition government who also use this refrain) who “criticise renewable energy for not being available when the sun doesn’t shine and wind doesn’t blow”.

“Batteries are a game-changer,” Lynham said, in stark contrast to prime minister Scott Morrison and Resources minister Matt Canavan, a Queensland Senator, who have both ridiculed batteries as being as useful as a “big banana” or something called the Kardashians.

Lynham noted that Queensland already had three large-scale batteries operating: at Lakeland Solar Farm in far north Queensland, at Kennedy Energy Park near Hughenden (although this one is not yet operating), and one at the University of Queensland in Brisbane.

Another in Townsville is expected to be operating next month.

“Queensland has seen $4.7 billion worth of investment in renewable energy projects since December 2016, creating 4200 jobs,” he said. “Queensland now has almost 5500 megawatts of renewable generation capacity.

“Batteries are next, and all of this investment demonstrates industry’s strong confidence in Queensland’s growing clean energy industry.

“It’s all ensuring that we remain well on track to reach our target of 50 per cent renewable energy by 2030.”

More battery storage projects are expected to be announced when the newly formed CleanCo announces its choices from the long-awaited RE400 program that is designed to underwrite more renewable and storage projects in Queensland. An announcement is expected within weeks, Lynham said on Wednesday.