Up to 75,000 South Australian homes remain without power as the state braces itself for more wild and destructive weather.

More homes lost power on Thursday as the Bureau of Meteorology (BoM) warned that an intense low-pressure system would send more wild weather across the state.

John Nairn, BoM regional director, told the ABC South Australia had only seen about half the rain expected to come.

A major political scuffle has erupted over whether renewable energy was to blame for the state’s total energy blackout on Wednesday.

Both Deputy Prime Minister Barnaby Joyce and Independent Senator Nick Xenophon controversially pointed the finger at South Australia’s transition to renewables such as wind power for the widespread havoc.

South Australian Premier Jay Weatherill disputed the claim, accusing them of “using the crisis” to air their anti-renewable agenda, while SA residents have described watching the “perfect storm” rip roofs off buildings.

On Wednesday, destructive twin tornadoes brought down about 22 transmission towers in the state’s north, tripping the interconnector with Victoria and shutting off power to the entire state.

Thousands still in darkness

About 18,000 State Emergency Service (SES) personnel were on standby for the massive cleanup, with the SES’ Terry Dwyer telling the ABC they had already responded to 1000 calls for help.

The Bureau of Meteorology described the storm as a “once in 50 years” event and warned the weather pattern would move towards Victoria and New South Wales on Thursday.

Premier Weatherill described the incident as a “perfect storm” and called an inquiry into the blackout.

By Thursday morning most of the 900,000 Adelaide metropolitan homes had power restored.

SA Power Networks spokesman Paul Roberts warned restoring power would be a “gradual process”.

People in the red shaded area are supplied by damaged transmission lines – unlikely to have power tomorrow. pic.twitter.com/r5Z35IYtgt

— SA Power Networks (@SAPowerNetworks) September 28, 2016

More wild weather is on the way, with an intense low-pressure system expected to cross the state on Thursday.

Bureau of Meteorology senior forecaster Brett Gage said a severe weather warning remained current for widespread parts of the state, with the west coast of Eyre Peninsula in for a “real buffeting”.

Power stations go down

The roof of a church in Blyth was blown off in the wild storms. Photo: ABC

Earlier in the day, equipment at Port Augusta was damaged during the storm, and Mr Roberts said some equipment had also been damaged around Blyth in the state’s Mid North.

“There was some kind of mini-storm event, or cyclone event, there that’s resulted in damage and that’s affecting customers around the region,” he said.

“We have a substation there that would supply out to several areas.”

Earlier, Telstra’s SA general manager spokesman Mark Bolton said mobile phone users should prepare for a loss of network coverage as towers and exchanges ran out of back-up power.

“We have had a few sites that have been identified as down, yes, so there are a few sites that are failing and probably more to come as the power outage is extended,” Mr Bolton said.

Traffic lights in Adelaide’s CBD have gone out after a power failure, due to severe thunderstorms. Photo: ABC

Premier Jay Weatherill urged people not to travel on the roads “unless absolutely necessary” during the blackout.

“[People] should continue to listen to [ABC Radio] on a battery-powered radio, or use social media to keep up to date as they possibly can,” he told 891 ABC Adelaide.

He said emergency services and hospitals were operating under their own generation.

“Our energy generation assets remain in tact, and there does not appear at this stage to be any damage to the interconnector with Victoria,” Mr Weatherill said.

He said the blackout had nothing to do with the recent closure of the Port Augusta power station.

“The system has behaved as it’s meant to behave to protect the national energy market,” Mr Weatherill said.

Some lights have been turned on in Adelaide after the blackout. Photo: ABC

Mr Frydenberg said more than 40 per cent of South Australia’s energy supply comes from renewable energy, but emphasised that was not the cause for the blackout.

“That does raise questions for the stability of the system — not just for supply, because when the wind is not blowing and the sun is not shining, electricity is not being generated — but also for the stability of the system,” he said.

A map on the SA Power Networks website shows outages across South Australia. Photo: SA Power Networks

South Australian Senator Nick Xenophon described the incident as unprecedented.

“This is a disgrace. How did this happen? How is an entire state blacked out?” Senator Xenophon told the ABC.

Coal is fuelling climate change and extreme weather, but some people want to blame renewables for SA's power outage. #SAstorms https://t.co/6oCr1PVgHk

— Australian Conservation Foundation (@AusConservation) September 29, 2016

South Australian Police Commissioner Grant Stevens declared the statewide power outage a major incident under the Emergency Management Act.

Dark skies over Adelaide as South Australia grapples with a state-wide power outage. Photo: ABC