Spot price volatility in South Australia on Wednesday evening 5th November 2025
A very short article with a snapshot from NEMwatch at 19:30 on Wednesday evening 5th November 2025 to mark some evening volatility.
Articles by 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.
Volatility in FCAS (Regulation and Contingency) prices in Tasmania on Wednesday 5th November 2025
A quick record of some volatility today in Regulation (and Contingency) FCAS prices in Tasmania on Wednesday 5th November 2025.
Brief unplanned power outage in central-western Queensland, on Wednesday 5th November 2025
A short note to record the brief unplanned outage in the Powerlink network (on Wednesday 5th November 2025) that impacted customers in the Longreach, Blackall, Barcaldine and Clermont area.
What happens when energy is free (part 2)?
It’s approaching 10 years since (in April 2016) we asked the question ‘What happens when energy is free?’. Well, this morning (Tuesday 4th November 2025) Minister Chris Bowen dropped the Media Release that speaks...
Large under-performance across Solar Farms as the main driver of frequency wobbles on Thursday afternoon 30th October 2025?
With respect to the ~17:00 period on Thursday 30th October 2025 (and the frequency drop, possibly outside the NOFB), we take a look at the Dispatch Error of individual Semi-Scheduled units to find patterns.
A second look at the frequency drop on Thursday evening 30th October 2025
We take a second look at the frequency drop that occurred at ~17:01 (NEM time) on Thursday 30th October 2025.
The return to service of Callide B2 and C4 in October 2025, following storm issues
Following this update on LinkedIn from CS Energy on Thursday 30th October 2025, we summarise outages at Callide B2 (two outages) and Callide C4 (one outage).
Loy Yang B1 returns to service after planned outage – not without a few wobbles (and frequency drop)
Loy Yang B1 has returned to service on Sunday morning 2nd November 2025 following a planned outage, not without some wobbles.
A quick look at Dispatch Error on Friday afternoon 31st October 2025, with the frequency drop
We’ve just noted the frequency drop on Friday afternoon 31st October 2025, and so take a look at 'Aggregate Dispatch Error’, to see if it's likely we are correct in our hypothesis - that...
A second look at the frequency drop on Friday afternoon 31st October 2025
Yesterday afternoon, we quickly noted the ‘Frequency drop on Friday afternoon 31st October 2025’. Now, we take a closer look to highlight the lowest point (outside of the NOFB).
Vales Point 6 returned to service Friday afternoon/evening 31st October 2025 after tube leak outage
A short record of the unplanned outage at Vales Point 6 - which came offline overnight into Tuesday 28th October 2025, and returned to service Friday 31st October 2025.
Frequency drop on Friday afternoon 31st October 2025
A short note with this snapshot of a 6-hour long frequency trace on Friday afternoon 31st October 2025, to capture what looks like another VRE-induced frequency wobble earlier this afternoon.
David Dixon speaks again about the large gap between aspiration and reality
Earlier on Day 2 at All Energy in the ‘National Electricity Markets’ session there were a number of interesting presentations, including one from David Dixon.
The ‘Reform of the NEM’ session at the tail end of Day 2 of All Energy 2025
A short note about today's graveyard shift session titled ‘Pushing Boundaries: Navigating Market Reform for a modern, efficient, and secure electricity system’ at All Energy. A session that was particularly worthwhile for me.
Frequency wobbles on Thursday afternoon 30th October 2025
A short article highlighting some frequency wobbles on Thursday afternoon 30th October 2025.
Direction for System Strength in NSW again–on Thursday 30th October 2025
In a repeat of yesterday, the AEMO has again directed for System Strength in NSW on Thursday 30th October 2025.
Comparing AggROT for (44x) Coal Units with AggROT for Semi-Scheduled units through the history of the NEM
On Sunday (following from the discussion at the NEMdev conference in Brisbane a few weeks ago, and leading into this week’s All Energy 2025 in Melbourne) I highlighted these ‘Two *big concerns* that we...
Another direction for System Strength in NSW (on Wednesday 29th October 2025)
It's day 1 of All Energy 2025 today (Wednesday 29th October 2025) , and the day will have already started - but I thought it would be topical to note another direction for System...
Frequency drop with trip of Callide B2 on Tuesday evening 28th October 2025
A short note to capture the trip of Callide B2 on Tuesday 28th October 2025 in the five minute period prior to 21:01 (NEM time) that day.
Sharp mainland frequency drop, with trip of CPP_4 on Sunday evening 26th October 2025
The Callide C4 unit tripped from 420MW in the 5 minutes to 18:36 (NEM time) on Sunday evening 26th October 2025, delivering a sharp drop in mainland frequency.