South Australia's statewide blackout could have been avoided if the settings on wind turbines had been different, the Australian Energy Market Operator says.
The operator has released its final report into the blackout on September 28 last year, when fierce storms brought down major transmission lines in SA's north.
AEMO says turbines at SA wind farms were still functioning properly during the extreme weather, which included tornadoes and lightning.
But it says nine of the wind farms switched off because of control settings that reacted to disturbances.
The loss of wind power boosted electricity flows through the interconnector between SA and Victoria so significantly that it tripped, shutting down SA's entire network.
AEMO says if the power generated by wind farms had not been lost it is likely the interconnector would have stayed on, along with lights in SA households.
"AEMO's modelling indicates SA would have remained connected to Victoria and the black system would have been avoided," the operator said in its report.
It said changes to wind turbine settings soon after the blackout have removed the risk of them turning off again if faced with the same disturbances.
The regulator's report includes 19 recommendations, which it said will be implemented by December.
Seven of the recommendations are new, including AEMO improving its forecasting for when wind speeds will exceed protection settings on turbines and changing how it operates SA when it is separated from the national grid.
Three of the recommendations have already been implemented, relating to more rigorous weather monitoring and improvements to AEMO's capacity to restart the SA energy system.
AEMO said the blackout has highlighted the challenges associated with keeping the electricity grid secure, particularly during extreme conditions, as Australia transitions to using more renewable energy sources.
It said traditional gas or coal power plants that are always on can no longer be relied upon solely to keep the nation's power grid strong and controlled and renewable power generation should play a role in ensuring such security.
"AEMO is working with industry on ways to use the capability of these new types of power generation to build resilience to extreme events," the report said.