Awoke this morning to a long stream of price SMS alerts triggered overnight for South Australia (and other particular keyword alerts for Market Notices, etc) due to the islanding event overnight.
Here’s a quickly annotated snapshot from NEM-Watch this morning:
Rough sequence of events:
|0:16 NEM time
|SA is islanded. The flow and import/export limits drop to zero. In a very quick scan I can’t actually find what causes this to happen.
|Immediately, constraint equations act to “constrain up” already operational units at Torrens and Quarantine in order that they can start to make up the power lost over the interconnect. Prices spike to $14,000/MWh
Peakers take longer to start up and cut in.
|AEMO notes that they have started directing participants. have not looked further at what happened here.
|AEMO notes that they have stopped directing participants.
Note that immediately prior to the separation, Victoria had been exporting to South Australia with prices in South Australia up around $300/MWh (not much wind blowing in South Australia, and obviously no solar overnight, leading to gas generators running to meet demand).
These generators were then able to ramp quickly to match the load lost from Victoria when those imports were no longer available.
Does not look like any load lost, thankfully…
Investigations and a formal report will follow.