This drop in frequency was shortly followed (when the next Dispatch Interval rolled around) with this ‘Notification’ widget alert from ez2view to show that the Callide C4 unit had tripped from 420MW in the 5 minutes to 18:36 (NEM time) on Sunday evening 26th October 2025:
Paul was one of the founders of Global-Roam in February 2000. He is currently the CEO of the company and the principal author of WattClarity. Writing for WattClarity has become a natural extension of his work in understanding the electricity market, enabling him to lead the team in developing better software for clients.
Before co-founding the company, Paul worked as a Mechanical Engineer for the Queensland Electricity Commission in the early 1990s. He also gained international experience in Japan, the United States, Canada, the UK, and Argentina as part of his ES Cornwall Memorial Scholarship.
Following on from Linton’s article (about the frequency drop at 15:40 on Monday 16th June 2025) we take a look at the largest harmful Dispatch Errors across the full fleet of units … and what do we find?
A follow-on to my earlier article of a couple weeks ago, looking at another instance where a team effort was required to counter a drop in system frequency following the loss of generation at a large power station (this time the single unit Kogan Creek power station – the largest single unit in the NEM).
To further understand the frequency drop we delve into the 4-second data (used for regulation FCAS contribution calculations) in this Part 2, looking at generating units (including BDUs).
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Statement on Callide Power Station availability – Updated
27 Oct 2025
Updated at 5.15pm
https://www.csenergy.com.au/news/statement-on-callide-power-station-availability