The Australian Energy Regulator has launched legal action against four wind farm operators over South Australia's statewide blackout in 2016.
The action in the Federal Court alleges AGL Energy Ltd, Neoen SA, Pacific Hydro Ltd and Tilt Renewables all breached the National Electricity Rules.
The allegations relate to the performance of wind farms during the severe weather event at the time which ultimately triggered the statewide power outage when transmission towers were brought down.
About 850,000 customers lost power during the blackout, with some in the state's north and on the Eyre Peninsula left without services for several days.
The regulator says each of the wind farm operators failed to ensure that their plant and associated facilities complied with their generator performance standard requirement to ride-through certain disturbances.
In addition, the AER alleges that the wind farm operators failed to provide automatic protection systems to enable them to ride-through voltage disturbances to ensure continuity of supply, in contravention of the National Electricity Rules.
"The AER has brought these proceedings to send a strong signal to all energy businesses about the importance of compliance with performance standards to promote system security and reliability" chair Paula Conboy said.
"These alleged failures contributed to the black system event, and meant that Australian Energy Market Operator was not fully informed when responding to system-wide failure in South Australia in September 2016."
Energy Minister Angus Taylor says it's important for the regulator to enforce market rules.
"We need to have reliable power in this country ... and that means all generators need to perform," he told reporters in Sydney on Thursday.
Mr Taylor says he's concerned about how Victoria will fare this summer, with closures of coal-fired power stations resulting in an increased reliance on renewable energy.
The minister says more power will be pumped into the system through the government's plan to underwrite new generation, including four projects in SA.
The AER is seeking declarations, penalties, compliance program orders and costs.
The action against AGL relates to the Hallett 1, Hallett 2 Hallett 4 and Hallett 5 wind farms.
In relates to Neoen SA's Hornsdale Wind Farm, Pacific Hydro's Clements Gap Wind Farm and Tilt Renewables' Snowtown 2 Wind Farm.
In a statement, AGL said it had previously considered that it had complied with its legal obligations in relation to the September 2016 events.
But it said it would review the allegations made by the AER and consider its position.
