South Australia has a serious problem. It is producing too much power. There were times on Sunday (Nov 21st) when generators had to pay to put power into the grid! South Australia (SA) “became the first gigawatt scale grid in the world to reach zero operational demand when the combined output of rooftop solar and other small non-scheduled generators exceeded all the local customer load requirements.”
It was a combination of plenty of sunshine & wind increasing output and mild weather reducing demand. After a number of records have fallen in the past few months, this was expected. The surprise is how fast things are moving. The challenge for market operators will be maintaining system strength and grid stability. Batteries, gas generators, and synchronous condensers all have a part to play in this.
At present, SA is able to export some of this excess power to the neighboring grid, in Victoria. It is expected that a link to New South Wales will be established by 2025.
“Eldridge notes that rooftop solar reached a record 95.6 per cent of total demand at 12.35pm, which is a record share. The previous record was 88.3 per cent on October 31. The record maximum output of rooftop solar is 1,301MW, which was reached on Thursday, November 4,” RenewEconomy writes.
SA has employed heavy curtailment at times because of the limits of the Victorian connection. Even so, wind and solar accounted for more than 62% of local demand over the last 12 months. The situation is likely to become more complex, as rooftop solar PV is expected to double over the next decade. Despite having the ability to switch off solar (this has only been deployed once so far), the Australian Energy Market Operator (AEMO) would prefer to use battery storage and appliances to soak up excess power. Wouldn’t it be great to be paid to use your car battery to store this excess energy?