The report, commissioned by Greenpeace Australia Pacific, shows that replacing the ageing and unreliable Hunter Valley power station with renewables backed up by batteries is 17% cheaper than replacing Liddell with gas and will result in fewer emissions.

Owners of Liddell and the neighbouring Bayswater power station AGL announced earlier this year they were prepared to invest in battery storage.

The company said it had lodged a scoping report with the NSW Department of Planning, Industry and Environment (DPIE) for a grid-scale battery system (850MW) to be located on the Liddell Power Station site, alongside the existing plant.

At the same time there has been a strong political push to replace Liddell's power input with gas and the Federal government's approval this week for the Narrabri gas project will only add to that pressure.

"Renewables firmed with storage solves the so-called 'energy trilemma' - affordable, reliable and cleaner power. This report demonstrates that by continuing to add renewables and storage to NSW's grid, the state will enjoy reliable power that's cheaper and much better for the environment than gas," senior advisor to the Climate and Energy College at Melbourne University, Simon Holmes à Court said.

"The closure of Liddell won't be like Hazelwood. With only five months' notice Hazelwood's closure came as a surprise to the community, workers, government and the power sector. The closure of Liddell, on the other hand, was announced in 2015 and AEMO's modelling shows that the market is on track to replace the lost capacity when the early 1970's era power station retires in 2023."

"The Federal Government's obsession with fossil gas is undermining private sector investment in our energy system. Economics and technology have overtaken the Federal Government's ideology. It needs to drop the obsession with gas, and let the market complete the clean replacement of Liddell - a transition that is creating jobs for the Hunter and securing a lower cost, reliable energy supply."

"Business, state governments of all stripes, and Australia's major trading partners are all ditching coal and gas for renewables and storage because the economics overwhelmingly win out."

With Liddell due to shut down completely by April 2023, the report modelled three scenarios for the National Electricity Market (NEM) to replace the 2000MW power station; [1]

1. Central Case: Current policies at time of publication i.e 2.6 GW of new renewables are added to the NEM by July 2023

2. Market Solution: In addition to the Central Case, the market builds an additional 1000MW of renewables

3. Gas Solution: In addition to the Central Case, 1000MW of new peaking gas is added to the NEM by July 2023

Reputex's analysis finds that the renewable-powered market solution, which would see 1000MW of new renewable capacity built to replace Liddell, offers the best value for money and makes the greatest impact on lowering Australia's emissions.

Under all three scenarios, reliability exceeds the state's Energy Security Target after the closure of Liddell.

Greenpeace Australia Pacific Head of Research and Investigations, Dr Nikola Casule said the Reputex report builds on growing evidence that clean energy should be at the centre of federal energy policy, driven by the declining cost and increasing reliability of renewables.

"This new report shows conclusively that renewable energy is the best option for replacing Australia's coal-burning power stations. Building new gas infrastructure is an expensive, unnecessary diversion that won't reduce emissions. Replacing coal with gas is like replacing a typewriter with a fax machine - they're both obsolete technologies that no longer meet Australia's energy needs."

"In the coming years, more and more ageing and unreliable coal-burning power stations like Liddell will close as they near the end of their operating lives and become too expensive to maintain. The operator of Australia's grid, AEMO, has already found that we can move to a renewable-powered grid without the need for any new gas."

"With a new Renewable Energy Zone slated for the Hunter that is set to create hundreds of jobs, a renewable energy replacement for Liddell sets the region up for a bright future. The

Federal Government needs to support the best way to secure Australia's energy supply, bring down prices and create future-proof jobs, replacing coal and gas with clean energy technology like wind and solar."