In 2019 about 16 percent of the electricity consumed is generated by wind and solar photovoltaics. By 2030 The Energy Security Council estimates that renewables will account for 40 percent of electricity use, driven by falling technology costs, government programs and consumer preferences.

“That size and speed of change [place] Australia in an international cohort that includes Ireland, California, Germany, Spain and Portugal,” the ESB wrote in its annual Health of the national electricity market report.

The uptake of renewables is also likely to drive down electricity prices, with both electricity and gas prices falling slightly relative to income levels and CPI as average energy use falls in line with solar uptake roof panels.

The decline was most notable in Queensland and South Australia, where there is high penetration of rooftop solar. The report also found that rooftop solar accounts for almost 5 percent of the national energy market, and that figure is expected to grow to 10 percent in 2030.

But climate change poses a threat to the security and reliability of Australia's aging energy grid, which has suffered due to the increased severity of summer weather events - particularly in Victoria, New South Wales and South Australia.

"The recent horrific bushfires highlight the importance of power system resilience as extreme weather events become more frequent and intense," the ESB wrote.

"This requires serious attention in the coming years, as new extreme events can be expected, including fire, flood and high temperatures." Australia's average temperatures have risen steadily over the past century... The specific specifications and cost of equipment that can withstand these conditions must be reviewed.'

The COAG Energy Council asked the ESB to recommend interim measures to improve the security and reliability of the system by March 2020.