As the Coalition backs away from a pledge to consider a climate change policy that the energy industry says it needs, a new study is projecting a rapidly growing mass electricity generator for Australia in the decades ahead: the public.

Consumers using rooftop solar panels and batteries will produce between a third and half of Australia's electricity by mid-century if the right policies are introduced, according to a roadmap from the CSIRO and power and gas transmission body Energy Networks Australia.

The two-year analysis also found an emissions intensity scheme for the electricity sector - a form of carbon trading that was to be considered by a government climate policy review until that plan was abandoned on Tuesday afternoon - would be the cheapest way to cut carbon dioxide emissions.

It suggests it could save customers $200 a year by 2030, while helping create a reliable electricity grid with zero emissions by 2050.