Energy a 'prime' issue after SA blackout

Another massive blackout in South Australia caused by destructive storms shows a reliable energy supply needs to be a "prime consideration" for governments.

Tens of thousands of South Australians remain without power more than a day after a destructive storm hit the state and badly damaged its electricity grid.

Talking to reporters in Melbourne on Thursday on behalf of the Turnbull government, Special Minister of State Scott Ryan expressed his sympathy to households and businesses that had suffered power loss and property damage.

He thanked emergency crews for their efforts before turning to the wider debate around power security.

"This illustrates again why security and reliability of electricity supply needs to be a prime consideration of all government policy," he said.

Electricity security and reliability has become a political flash point after a series of tornadoes caused a sequence of faults, plunging SA into darkness in September.

There are also concerns about Victoria's future energy capacity with the imminent closure of the Hazelwood coal-fired power station.