The research from The Australia Institute has "surprised" energy policy lead Dan Cass who says it proves coal power is not the linchpin as it was once argued to be.

"Clearly, batteries will be the most important technology keeping the grid secure as coal fired power stations retire," he said.

"The last refuge of the coal lobby has been that coal power is vital to keep the grid secure and this study shows that is not the case."

For an energy grid to function securely, it needs to keep frequency and voltage within safe limits, the study outlines.

Historically this has been the role of coal, gas and hydro power stations, and it suggests new technologies can provide 'fast frequency response' and voltage control to keep the grid secure.

Mr Cass said he expected the study to show clean technology was capable but would be expensive "like solar was 10 years ago".

"You're always looking into the future and then you realise the future has already arrived ... batteries are already here doing frequency control services, and cheaper than coal and gas every did," he said.

Key findings in the report show batteries and demand response provided more than a third of all frequency control markets in the last quarter of 2020, despite comprising just 0.5 per cent of the grid's generation capacity.

It states EnergyAustralia's newly announced 350 MW battery is likely to be able to provide at least three times the inertia capacity of the closing 1,480 MW Yallourn coal power station.

As well as addressing the technical challenges of grid security and reliability, Mr Cass hoped the economic augment for cheap clean power would help overcome political hurdles.

"I'm hopeful that even in political parties where there's some resistance to change, they'll see the case is so compelling that it is now time to redesign the grid for the emerging technologies," he said.

The research was written by leading energy economist Professor Bruce Mountain and battery expert Dr Steven Percy from the Victorian Energy Policy Centre.

"Renewables already create the cheapest electricity in the market and the last leg the fossil fuel industry had to stand on was the security services they have historically provided," Professor Mountain said.

"Now we can see that even those services are being delivered in a more reliable and affordable way by renewable energy and that trend will only accelerate in the future."

A discussion paper by Mr Cass summarises the findings and implications for the NEM redesign project, which state energy ministers are due to debate in June 2021.

"Coal power stations are closing and being replaced by clean energy but there is no national plan for replacing the security services that are provided by coal," he said.

The research was commissioned to assist the Energy Security Board's redesign of the NEM.

Australian Associated Press