As another case of frequency disruption on the mainland grid, we spotted this trend occurring just before midday on Friday 29th August 2025:
No time to look further, at this point.
About the Author
Paul McArdle
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.
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A second quick look at the drop in NEM Mainland Frequency on Tuesday 12th November 2024.
These sorts of excursions were so rare a few years ago, and now it’s just another week.
I feel sorry for all those who have to monitor frequency excursions and evaluate Unit response to prove compliance nowadays. Just about a full time job!