Dr Kerry Schott says the growth of renewables is presenting challenges and opportunities

While the rooftop solar boom was undoubtedly helping to drive bills and emissions down, it also had the potential to wreak havoc on power grids.

The Hunter has an average rooftop solar penetration of 21 per cent. However, homes in Perth and Brisbane and Adelaide have a rooftop solar uptake of about 30 per cent.

"In the middle of the day the power demand on the grid is zero," Dr Schott told Friday's Hunter Business Chamber luncheon.

"If you are running a distribution company and power demand goes from reasonably high levels in the breakfast peak to nothing at noon, then it becomes difficult to manage."

In addition to rooftop solar, the rapid expansion of large-scale renewable projects combined with the lack of an orderly transition policy had resulted in a recipe for chaos in the energy industry.

The Newcastle Herald reported this week that the Hunter is among the country's large-scale renewable energy hotspots with several billion dollars worth of projects in the pipeline.

They include a 250 megawatt wind farm at Bowman's Creek, a 250 megawatt pumped hydro scheme at Bells Mountain, a 250 megawatt gas-fired power station at Tomago and a 62 megawatt solar farm at Vales Point power station.

"Companies have been subsidised in one way or another to put in wind and solar and it is coming at a pace that is faster than anywhere else in the world," Dr Schott said.

"While in some places our percentage of renewables might look low, to get where we are now from where we were has occurred at an absolute rocket rate."

This renewable energy produced from these technologies was having a "momentous" impact on the energy market.

Coal plants that have traditionally earned a stable profit during the day now rely heavily on peak periods during the night or when there is no wind.

"The impact of that on coal plants is that they are likely to retire earlier than perhaps thought previously because of the financial viability that they find themselves in. While we have a very aged coal fleet, we have also got one that is struggling to remain financially viable," Professor Schott said.

Despite that, Dr Schott said coal was likely to remain part of the energy technology mix for "a long time"

Dr Schott's presentation coincided with a call from Origin Energy chief Frank Calabria for the introduction of a national energy policy to help boost investment in batteries, pumped hydro and gas plants.

"The industry desperately needs a strong signal to invest in other technologies to support our rapid uptake of wind and solar," he said on Friday.

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