Frydenberg questions SA grid amid blackout

Elise Scott

Federal Environment Minister Josh Frydenberg has questioned the stability of the South Australian electricity grid following a state-wide power blackout in the midst of a major storm.

But South Australian Premier Jay Weatherill denies the outage has anything to do with the state's reliance on intermittent renewable energy and the recent closure of its last coal-fired power station.

More than one million homes are without power and the hospitals across the state are operating on back-up power after the state lost electricity about 4pm on Wednesday.

Mr Frydenberg says the state-wide blackout is "clearly not adequate" and wants to convene a meeting of the COAG energy council to make sure it never happens again.

"The ramifications are huge for so many people involved," he told ABC Television on Wednesday evening.

The outage is understood to have been caused when the storm knocked out transmission towers, cutting the frequency to the system.

Mr Weatherill says that tripped the system, which shut down and severed interconnection with the Victorian electricity grid - South Australia's only connection to the national electricity grid.

South Australia relies on renewables - mainly wind power - for more than 40 per cent of its power.

But the premier insists that isn't the cause of the outage and says the same "dramatic event" would have shorted any system in the world.

"This is the system protecting itself," he said, adding it had nothing to do with the May closure of Port Augusta's coal-fired power station.

"For people to be saying those things without being appraised of all the facts shows people are using this to play politics."

Mr Frydenberg said the system's stability must be questioned after the outage, but cautioned that the underlying cause was the storm.

"Questions are raised by the virtue of the increasing amount of renewables," he said.

It's not clear how long it could take for power to be restored across the state, but some homes could be without power until Thursday.