AGL seeks approval for 500MW big battery at site of Liddell coal generator

AGL Energy has kick-started the transformation of the ageing Liddell coal-fired power station, lodging initial development documents for a new big battery of up to 500MW – more than three times the size of the Tesla big battery in South Australia, which remains the biggest in the world.

AGL is also going to lodge a planning application for a big battery at the site of the Torrens Island gas generator in South Australia, which like Liddell is coming to the end of its life. There are already three big batteries in South Australia, with a fourth soon to be commissioned.

The 1,680MW Liddell power station – one of biggest in NSW – has been flagged for closure by AGL in 2023, despite repeated calls by the federal government to keep it open. AGL has intentions to repurpose the existing infrastructure at the Liddell site, once the coal power station is decommissioned to support the construction of new generation and storage infrastructure.

The preferred plan for the Liddell power station site developed by AGL includes an initial big battery installation of 150MW, but the planning approval it is seeking from the NSW government is for a big battery of up to 500MW in total.

AGL will look to develop a similar sized battery at the Torrens Island site, and is considering a battery between 100MW to 150MW in capacity for its initial stage.

The hours of storage – expressed in megawatt hours – is yet to be determined, but the Liddell battery is set to be overtake the Tesla big battery at Hornsdale in South Australia – currently being upgraded from 100MW/129MWh to 150MW/194MWh and setting new records in testing –  although much bigger batteries are being built or are planned in the US.

AGL says that it has already approached a number of suppliers to tender for the supply of the battery systems to be installed at the Liddell site and has lodged an initial scoping document with the NSW Department of Planning, Industry and Environment.

Its newly appointed chief operating officer, Markus Brokhof, said that the commercial competitiveness of large-scale battery storage had improved dramatically over the last decade, allowing the energy company to expand its investments in the technology.

“Battery storage is critical to enhance the energy system’s flexibility and support the ongoing integration of renewable sources to the NEM,” Brokhof said in a statement.

“It removes one of the biggest limiting factors of renewables, by providing electricity anytime but particularly during peak demand. For a long time AGL led the way in renewable investment. As more renewables come into the energy system, we need to make sure we are supporting the development of storage and firming capacity, like grid-scale batteries,”

AGL operates a 1,280MW gas fired generator at the Torrens Island site, which has now been operating for more than 50-years. AGL shelved plans to mothball the ageing generator, to provide additional generation capacity to the South Australian energy market, but it is expected to be progressively closed over the next two years after a replacement was constructed at Barker Inlet.

The announcement comes just a day after AGL told shareholders during its annual earnings update that it had set a target to grow its battery storage and demand response programs to up to 1,200MW in available capacity.

By 2024, AGL is targeting the addition of 850MW of new large-scale battery storage capacity, as well as 350MW of coordinated distributed energy resources, including residential battery storage and demand response capacity. The successful achievement of these targets has been tied to senior management bonuses as part of AGL’s incentives initiative.

“We believe Australia has an opportunity to be a low-emissions, energy superpower in the years to come which is what we have set out to achieve through the delivery of our commitments under our Climate Statement,” Brokhof added.

“We are committed to helping create an energy future that is smart, efficient and affordable for our customers. This project will not only enable those outcomes but in doing so set the stage for a battery era.”

In addition to the Liddell battery, AGL is progressing plans to add a 100MW/150MWh battery next to the proposed Wandoan solar farm in Queensland, and up to 200MW/400MWh of battery capacity spread across four sites in partnership with the Maoneng Group, including a 50MW/100MWh battery next to the Sunraysia solar farm.

The company is already operating a 30MW/8MWh battery system at Dalrymple in South Australia, adjacent to the Wattle Point wind farm (pictured above).

AGL said that it was considering additional locations for the construction of large-scale battery storage, with further announcements likely soon.