2016 South Australian blackout

The South Australian blackout of 2016 was a widespread power outage in South Australia that occurred as a result of storm damage to electricity transmission infrastructure on 28 September 2016. The cascading failure of the electricity transmission network resulted in almost the entire state losing its electricity supply. Kangaroo Island did not lose its supply, as the Kangaroo Island power station had been built to supply the island in the event that the power cable under Backstairs Passage might fail, so the island was self-sufficient for electricity when the mainland grid failed.

On the day of the failure, South Australia experienced a violent storm reported as being a once-in-50-year event. There was gale force and storm force wind across wide areas of the state. It included at least two tornadoes in the vicinity of Blyth, which damaged multiple elements of critical infrastructure. The state was hit by at least 80,000 lightning strikes. The wind damaged a total of 23 pylons on electricity transmission lines, including damage on three of the four interconnectors connecting the Adelaide area to the north and west of the state.

The South Australian power grid is operated by ElectraNet and connected to the National Electricity Market via two interconnectors to Victoria. These are the Heywood interconnector (recently upgraded to 650MW at 275kV) in the southeast of the state and the Murraylink (220MW at 150kV) HVDC further north, connecting Berri to Red Cliffs in Victoria. The Heywood interconnector had been down for upgrade earlier in the year, and was initially blamed for the widespread outage.

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