North-south switcheroo as solar conditions swing opposite directions over Autumn 2025
Rainfall and cloud cover has split Australia this autumn, delivering a mixed bag of solar irradiance conditions for solar farms across the NEM.
Detailed Analysis
Examples of self-forecasting behaviours – part 5 – afternoon underestimations
A sequence of afternoon intervals stand out because the forecast appeared to be biased low – self-forecasts suddenly dropped roughly 30-40 percentage points and then increased a short time later.
Examples of self-forecasting behaviours – part 4 – avoiding SDC periods
Theoretically, if a self-forecasting system never offers forecasts for more than 60% of intervals it may perpetually skip the performance assessment and the system could continue for use unsuppressed.
Examples of self-forecasting behaviours – part 3 – lunar megawatts
In another style of biasing a self-forecast, "lunar megawatts" represent an expectation of solar farm generation at night when it really should be zero.
Examples of self-forecasting behaviours – part 2 – relative accuracy
The forecast differences would contribute to improved lower RMSE and MAE scores, relative to AWEFS_ASEFS, in the weekly performance assessment.
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 claim on social media.
NEMDE nightmares – parallel pathways and clashing constraints
Prompted by a question by a client in a training session for a new ez2view user, guest author Allan O'Neil has written 2,940 words to explain the price outcome in one particular dispatch interval for one particular region (19:05 on Tuesday 11th February 2025 in...
The state-of-charge for 2024: The highs and lows of the big battery boom
Following on from a similar review this time last year, Dan provides an updated look at the economics and performances within the NEM's big battery fleet, making use of our recently released GSD2024.
Indicators of solar farm performance with GSD2024
Seeking indications of possible performance at solar sites announced in the CIS tender of 2024, we inspect statistics of nearby solar farms using the GSD2024.
New FCAS resources dominate enabled levels in 2024
Using the latest GSD – GSD2024 – we take the opportunity to reflect on FCAS enablement and how enabled levels are changing between technology types.
Keeping up with the curtailment 2024: A little? too much? or much ado about nothing?
Drawing from our freshly released GSD2024, Dan provides some deeper insights into curtailment in the NEM, beyond the headline totals that were a topic of much online discussion earlier this week.
The GSD2024 (Generator Statistical Digest 2024) is released
It's Wednesday 5th February 2025, and we* are pleased to release the GSD2024 … following a focused effort across both teams over the period since the changeover from 2024 into 2025. Some details here, more coming in subsequent articles ...
Interconnector intricacies: double and triple auto-clamping of pesky negative residues
Dan looks at some recent and peculiar auto-clamping behaviour of interconnectors, and walks through the market arrangements causing these occurrences.