Malcolm Turnbull has admitted windmills didn't cause a South Australia-wide blackout last year as the renewable energy debate heats up.

On the same September evening power went out across the state last year, Energy Minister Josh Frydenberg said the blackout raised questions about the virtue of increasing the amount of renewable energy.

The next day, Mr Turnbull blasted the states for setting aggressive and unrealistic renewable energy targets.

Now, emails released under freedom of information show the prime minister's own officials were advised that morning the problem had not been SA's heavy reliance on wind power.

"[Electricity market regulator] AEMO's advice is that the generation mix (ie renewable or fossil fuel) was not to blame for yesterday's events - it was the loss of 1000 MW of power in such a short space of time as transmission lines fell over," one email read, Fairfax reported.

The prime minister insisted on Monday the introduction of a massive amount of wind energy made the SA grid very vulnerable.

"Of course windmills did not cause a blackout. The blackout, as I have said many times, was caused by a storm breaching transmission lines," he said.

"That's perfectly obvious."

Mr Turnbull insisted renewables have a very big place in Australia's energy mix.

But he said wind and solar had one specific characteristic: wind didn't blow all the time and the sun wasn't always shining.

"So you have to have either storage or backup power to keep the lights on and to ensure that energy is secure and affordable and you meet your targets," Mr Turnbull said.

Mr Frydenberg said the released email was "exactly consistent" with what he, the prime minister and others said at the time.

Bu opposition energy spokesman Mark Butler has urged Mr Turnbull to come clean and admit he's been playing politics with a very serious energy crisis.

"It is quite clear from today's revelations the prime minister made a deliberate decision to ignore that advice and lie to the Australian people about the cause of this very serious event," he told reporters.

"Not only did he lie to the nation, he lied to the nation during an emergency, while state emergency officials, people from our defence forces, were out in the field protecting the community from an ongoing risk caused by this extraordinary storm event which also led to very significant flooding."

Labor colleague Sam Dastyari said the power problems on the east coast over the weekend had nothing to do with renewables.

He acknowledged there were problems in the market but said the government is running a scare campaign.

"It just happens to not be on the basis of facts," he said.