‘N-MNYS_5_WG_CLOSE’ constraint set invoked, because of unplanned outage of Yass – Marulan 5 330kV line
At 16:16 (NEM time) on Wednesday 10th December 2025 there was an unplanned outage of Yass - Marulan 5 330kV line.
All Posts
Yo-yo-ing of ‘Market Demand’ in South Australia – on Wednesday 10th December 2025
Whilst today saw the release of the draft 2026 ISP, some 'challenges of the future' are already here today - such as the increasingly large and common gyrations in 'Market Demand' seen in South...
Another example of (presumably VRE-induced) weakness in mainland frequency – Wednesday afternoon 10th December 2025
We can see that the frequency weakened late in the afternoon (Wednesday 10th December 2025), falling down towards the Normal Operating Frequency Band.
Victorian Auditor-General’s report ‘Managing the Transition to Renewable Energy’
We thought it might be useful to point directly to the 61-page report ‘Managing the Transition to Renewable Energy’ by the Victorian Auditor-General.
AEMO releases draft of 2026 ISP
Today (Wednesday 10th December 2025) the AEMO has released the much-awaited* draft of the (upcoming 2026 iteration of the) Integrated System Plan .
The long-term trend of forecast errors for daily peak demand in QLD over the past seven summers
A look at how AEMO’s short-term forecasts have performed at the daily peak in Queensland over the past seven summers — and how that performance is changing as rooftop PV grows.
Wellington North Solar Farm back to 94 ELAV compared to 104 in total
Third article in the series, we take a look at the specifics of how much of Wellington North Solar Farm is back online (at Tuesday morning 9th December 2025).
Early morning price volatility in South Australia on Monday 8th December 2025
There was some early morning price volatility in South Australia on Monday 8th December 2025 - a social media update from Michael Caravaggio from EPRI internationally prompts this article.
Wellington North Solar Farm back online (late Sunday afternoon 7th December and) Monday 8th December 2025
The Wellington North Solar Farm (which came offline Sunday 7th December 2025 due to grass fire) is back online.
Wellington North Solar Farm offline in ST PASA data from Saturday 6th December 2025, following grassfire
Just after 13:00 (NEM time) on Saturday 6th December 2025, the Wellington North Solar Farm came offline following a grass fire onsite.
Guest Authored Posts
Runway cost allocation – ready for liftoff?
Allan O'Neil unpacks a proposal under consideration by the AEMC to apply “runway” cost allocation to contingency FCAS, explaining how this could materially change who pays for frequency security in the NEM.
What the hail is happening with Brisbane’s weather?
Anthony Cornelius from WeatherWatch explains the climate drivers behind Southeast Queensland’s unusually intense 2025 hail season — context that matters for those tracking how extreme weather is evolving and influencing the energy market.
Detailed Analysis
Examples of self-forecasting behaviours – part 1 – biasing
In today’s article (part 1 in this series) we present an example of biasing (at an unnamed solar farm), which we find aligns with FCAS cost mitigation.
Adoption and use of dispatch self-forecasting for solar units, Q1 2025
47% of dispatch intervals for semi-scheduled solar units are seeing a self-forecast used. When there are gaps, was the unit suppressed?
Is the price right? A historical exploration into the NEM’s price cap
Dan dives into the history of the NEM’s market cap and explores how high-end prices contribute to regional settlement costs and cap payouts.
Adoption and use of dispatch self-forecasting for wind units, Q1 2025
We summarise how wind units are using self-forecasting to-date. The analysis leads us to consider where upcoming market change may lead the industry.
Four days in the NEM in four minutes
Dan shares a short time-lapse video which demonstrates four days worth of activity in the NEM, highlighting the impact of network congestion in QLD and NSW.
How did Cyclone Alfred impact electricity demand?
By day-end on the Friday the 7th demand levels were down more than 40% in the Gold Coast. Other areas were also impacted.
Three headline observations, about the use of proxies for System Frequency in Frequency Control mechanisms
Various authors have shared articles about frequency, frequency control and Regulation FCAS in recent times (including 6 from Linton). Here's three things that jumped out to me in these pieces of analysis.
Is VRE forecastable? (Part 1 in what might be a series)
Over many years we've invested deeply in analysing the nuanced answer to the question 'Is VRE Forecastable?'. This article (which has almost been posted many times before) is triggered today by yet one more...