South Australia has been effectively powered by green energy for a week, with one expert predicting it could extend to a month by early next year.
From December 12 to 19, National Energy Market data showed wind and solar contributed on average 103.5 per cent towards the state's energy demand.
No coal was used during the period, but gas accounted for 5.9 per cent of electricity when renewable sources were not enough to power the state at points at night.
The state's connection to the national electricity grid saw it import three per cent of its net energy demand.
The average cost of a megawatt hour dropped to -$26.35.
Premier Peter Malinauskas said it was a significant step.
"That has never occurred ever before in the history of the country," Mr Malinauskas said.
"We understand that it's also a world-first for an entire jurisdiction to have all of its energy needs met across a seven-day period exclusively by renewables," he said.
"That shows you the potential of having renewables in the system, giving us an energy transition but also to a low-cost future when it comes to power."
Expert expects more milestones
Head of the Victoria Energy Policy Centre at Victoria University, Bruce Mountain, said it was another step on the renewable energy journey.
Mr Mountain said he was confident that no other jurisdiction of South Australia's size would have achieved the renewable energy result of the past week and he expected more to come.
"A major milestone would be an annual measurement — South Australia getting more energy from wind and solar than all others and that will happen probably in about four to five years time," Mr Mountain said.
He said that South Australia could expect to see the state powered using green energy for a month by early next year.
"This coming March ... we'll be knocking on the door of 100 per cent in SA," he said.
The record was reached at the same time a new solar and battery storage farm near Murray Bridge in South Australia's Murraylands was opened.
The Woods Point farm is designed to generate 9,000 megawatt hours of solar energy, enough to power more than 1,000 homes each year and prevent about 10 million tonnes of carbon dioxide being added to the atmosphere.
It's one of three solar storage projects in South Australia being developed by Sustainable Energy Infrastructure and Yates Electrical Services Group with the others to open at Port Wakefield and Padthaway.
The three projects will also store three gigawatt hours of energy into the grid if and when needed.
