Police direct traffic around the CBD in Adelaide on Wednesday afternoon. Credit:AAP More than 18,000 State Emergency Services volunteers were on the ground across the state responding to hundreds of calls for help, with reinforcements on their way from Western Australia. Premier Jay Weatherill said the storm took down three transmission lines and nine towers in the Port Augusta region, forcing the electricity connection between South Australia and Victoria - known as an "interconnector" - to be shut down. Wind turbines, which make up an estimated 40 per cent of the state's power generation, were unable to operate as winds were too high, South Australian senator Nick Xenophon said. Mr Weatherill told media it was the "usual protocol" to isolate South Australia from the National Electricity Market in a situation where there is a "large frequency drop".

The storm passing through Woomera in SA's north on Wednesday. Credit:Bureau of Meteorology He said the state's "backup baseload generation" was beginning to restore power, however that was a gradual process. The operators of SA's high-voltage power network, ElectraNet, were in an emergency meeting on Wednesday afternoon to determine a solution. Adelaide was battered by the storm on Wednesday. Credit:Twitter/@brittaaahhny National energy and resources minister Josh Frydenberg said high-voltage transmission towers were blown over in the state's north as lightning struck a power station, creating a "perfect storm".

"The combination of these events, and indeed other events, have led to a frequency surge, an electricity surge, across the interconnector," he said. He proposed bringing together the nation's energy ministers as soon as possible in a Council of Australian Governments meeting to determine what happened and ensure it was not repeated. The SES advised people to "stay at home if you can", saying electric trains and trams had come to a halt across Adelaide.

Adelaide Airport was able to run on back-up power after a brief blackout, but travellers were told to expect delays. About 5.30pm, residents were told to conserve power to their mobile phone battery and prepare for extended outages. Residents were also told to switch off all heating, cooking and other appliances that were in use when the power went out. Two severe storm fronts swept across SA on Wednesday, the first hitting Adelaide around lunchtime and the second about 3.30pm. The power went out across the state about 3.45pm, when there was heavy rain, lightning and thunder over the capital. The town of Cleve, on the central Eyre Peninsula, was among the hardest hit. Other towns including Gawler, Kapunda, Clare and Balaklava were also hammered by the storm, which dumped large hail over the region.

Kim Westcott, a Meteorologist with Fairfax Media's Weatherzone, said 130,000 lightning strikes hit the state from midnight to 5pm. The strikes, part of a cold front, mainly hit in the state's south-east, within 300 kilometres of Port Augusta. "In behind this lightning-intensive system we have a really quite intense low-pressure system, so we are looking at damaging wind gusts," Ms Westcott said. The Bureau of Meteorology warned wind gusts up to 140km/h could be experienced, with isolated rainfall up to 100 millimetres. By Wednesday evening, the highest gust had been recorded at Snowtown, which experienced 104km/h winds in the mid-afternoon and 26 millimetres of rain in an hour.

High winds and rain are expected to continue on Thursday, as another low pressure system moves over the state. However, conditions are expected to "rapidly improve" on Friday. Senator Xenophon said the situation was a "disgrace" and he was worried for those who relied on power for medical equipment in their homes. "How did this happen?" Senator Xenophon asked. "This is unprecedented in this nation. We need answers. There needs to be an independent inquiry. "I can't believe that my state is in darkness at the moment. This should not have happened, and if heads should roll, so be it." The Clean Energy Council, the peak body for renewable energy, said no connection had been established between clean energy and the blackout.

"The resulting power outage is obviously frustrating for everyone in the state, but it is important to note that this could have happened in any state given today's weather conditions," Clean Energy Council policy manager Tom Butler said . "Despite the extensive effort put into planning for emergency events by the electricity grid operator, not every event can be predicted." Loading There were no implications for other states from the extensive blackout. with Fergus Hunter