Loss of ~2000MW of demand in Queensland on Tuesday 25th May

A quick snapshot from NEMwatch at 14:20 today highlighting the loss of approximately 2000MW of demand this afternoon – dropping the level of Scheduled Demand down to 3,775MW:


The AEMO Market Notice highlighted says:


From :              AEMO
To   :              NEMITWEB1
Creation Date :     25/05/2021     14:10:44


Notice ID               :         85926
Notice Type ID          :         POWER SYSTEM EVENTS
Notice Type Description :         Emergency events/conditions
Issue Date              :         25/05/2021
External Reference      :         Non-credible contingency event – Qld region – 25/05/2021


Reason :


Non-credible contingency event – Qld region – 25/05/2021

At 1344 hrs the Callide C Power station generating units C3 and C4 tripped.

AEMO did not instruct load shedding.

AEMO has not been advised of any disconnection of bulk electrical load.

The cause of this non credible contingency event is not known at this stage.

Manager NEM Real Time Operations




We can see the loss in generation output in the chart at the bottom of the NEMwatch snapshot.


PS…  at 15:09 this series of tweets from CS Energy provided more context to an origination of the problems:


I will see what I can do for a more detailed ‘Part 2’ Case Study of this event later at WattClarity.

About the Author

Paul McArdle
One of three founders of Global-Roam back in 2000, Paul has been CEO of the company since that time. As an author on WattClarity, Paul's focus has been to help make the electricity market more understandable.

Leave a comment

Your email address will not be published.