Switching Australia to 100 per cent renewable power within decades could end up costing the same as continuing to use fossil fuels, a federal government study suggests.

Modelling by the Australian Energy Market Operator shows sourcing 100 per cent of power from solar, wind and other clean sources would be technically viable by 2030, albeit with the cost ranging from $219 billion to $252 billion. But a "community summary" quietly published this month has rekindled debate by saying a massive renewable expansion would be no more expensive than expanding conventional energy.

The economics are shifting in renewable energy's favour. Credit:Andrew Sheargold ARS

"We're exposed to rising carbon prices, we're exposed to rising gas prices," said Jenny Riesz, a research associate at the Centre for Energy and Environmental Markets at the University of NSW. "What this [summary] is saying that for around the same price, you can build 100 per cent renewable energy and completely protect yourselves from all of those risks."

Based on the AEMO study and other modelling by Treasury, the CSIRO and the University of NSW research, the summary concluded: "Indicative wholesale electricity prices generally fall within a reasonably narrow range of around $100 - $130 per megawatt-hour in 2030 and around $110 - $150 per megawatt hour in 2050." Consumers, who have seen electricity prices rise about 70 per cent over the past four years, may find the price trajectory confronting, whether based on renewable energy or not. NSW and Victoria have wholesale power prices of just under $60 per MWh.