South Australia separates from NEM, again, as interconnector troubles return
Australia has been re-syncronised with the rest of the National Electricity Market and power flow has been restored via the Heywood terminal.
The South Australian electricity system has again become separated from the rest of the National Electricity Market, with system operator AEMO confirming that the state was again islanded on Monday.
In a notice to the National Electricity Market, the AEMO confirmed that South Australia had separated from Victoria, with the connection between the two states, via the Heywood Interconnector, no longer functioning and electricity is no longer being transferred between the two states.
AEMO told RenewEconomy that they are currently investigating the latest cause of the separation, but the market operator also confirmed that there were no predicted supply shortages within the National Electricity Market.
”The root cause of the separation is currently under investigation by AEMO and the asset owner, AusNet Services,” an AEMO spokesperson said.
“There are currently no Lack of Reserve (LOR) conditions across the entire National Electricity Market.”
In the immediate aftermath of the latest disconnection at the Heywood interconnector, wholesale electricity prices in the South Australian region spiked to more than $5,000 per MWh, and then fell to negative $300 per MWh, as the market operator worked to maintain a balance of supply without the ability to send excess wind and solar generation out of the state.
According to OpenNEM, more than 50 per cent of South Australia’s power was being supplied by solar energy, with an additional 20 per cent being supplied by wind power just prior to the separation.
However, following the latest separation, generation has been cut back from wind generators and large-scale solar projects, with the bulk of generation being supplied by rooftop solar and a ramp-up of gas generators.