This was due in part to a fall in wholesale power prices which are currently at a five year low according to the Australian Energy Regulator.

Increased use of renewables is given along with lower fuel costs for the drop in power prices.

On the back of that earning advise advise yesterday today AGL announced it had lodged a scoping report with the NSW Department of Planning, Industry and Environment (DPIE) for a grid-scale battery system to be located on the Liddell Power Station site, alongside the existing plant.

In a release to to the Australian Stock Exchange the company says the Liddell Battery is part of the 850MW multi-site integrated battery system AGL targets to develop by FY24 as announced in its FY20 Results, and is in support of its Climate Statement commitments to continue to invest in new sources of electricity supply.

AGL Chief Operating Officer, Markus Brokhof said over the past decade battery technology has evolved rapidly and is now at an investment level that allows AGL to lead the transition to decarbonisation in Australia.

"Battery storage is critical to enhance the energy system's flexibility and support the ongoing integration of renewable sources to the NEM," Mr Brokhof said.

"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's support of grid-scale battery projects include Wandoan (100 MW), Maoneng (4 x 50 MW) and Dalrymple (30 MW).

"We believe battery technology is now at a level that allows AGL to lead in Australia's transition to a smarter and more efficient energy future," Mr Brokhof said.

Planning applications are also being developed for a battery connected to Torrens Island Power Station site in Adelaide with other sites under consideration.

To support delivery of this target AGL has invited select suppliers to tender for the procurement of the grid-scale batteries included in this system.

Mr Brokhof said AGL is getting on with the business of transition and continuing to investigate how to incorporate new technology options that will provide flexible generation and storage.

"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," Mr Brokhof said.

"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."

The investment in batteries is part of AGL's ongoing commitment to firming technology and is in direct alignment with the Federal Government's National Technology Investment Roadmap and consistent with AEMO's 2020 Integrated System Plan released in July.

The Nature Conservation Council says it welcomes AGL's plans to significantly expand its investment in grid-scale storage.

"The symbolism of converting Liddell coal-fired power station site into a major battery for clean energy storage could hardly be more powerful," Nature Conservation Council Chief Executive Chris Gambian said.

"AGL clearly sees the end of coal as inevitable. The only question now is the speed of the transition.

"AGL has also put what should be the final nail in the coffin for the expensive, dirty and unnecessary Narrabri coal seam gas project.

"The science tells us that NSW and Australia have to end coal-fired power generation by 2030 to be on track to meet the Paris targets.

"If the government and business stick to their current plans, they will miss that deadline by 20 years.

"After the bushfire summer from hell that we just lived through, it is clear we cannot afford to delay.

"We applaud AGL's announcement today, but we urge all companies and governments to lift their level of ambition so Australia has 100% clean energy by 2030."