Supply-side capacity in the NEM over the next 10 years (v1)
Capacity of batteries and hydro is covering capacity lost with retiring thermals. That is, assuming the anticipated developments do eventuate.
semi-scheduled generation
402 different stories – Semi-Sched units during both frequency spikes (Fri 10th and Sat 11th April 2026)
We start with this unbundled listing of 402 discrete stories about the performance of Semi-Scheduled units (115 solar & 86 wind) units on Friday 10th and Saturday 11th April with the frequency spikes.
Across 201 x Semi-Scheduled units, which were the biggest over-performers (Saturday afternoon 11th April) driving the frequency high?
With the advantage of 'next day public' data we look at 'Dispatch Error' (for all 201 Semi-Scheduled units) at 14:20 on Saturday 11th April 2026 to see what drove the frequency spike outside of the NOFB. There was a big imbalance...
A quick look at Dispatch Error for each individual Wind Unit (at 03:05 on Thursday 2nd April 2026)
In Part 5, we’ll look at Dispatch Error for all Wind Farm Units (i.e. the Semi-Scheduled ones only) at 03:05 on Thursday 2nd April 2026, following the trip of Kogan Creek.
Delving deeper, into periods of under-performance across Semi-Scheduled Solar Farms on Tuesday 27th January 2026
This is the 1st of two articles today … this one specifically focused on Large Solar (i.e. the Semi-Scheduled units) and the aggregate Dispatch Error across all 288 dispatch intervals on Tuesday 27th January 2026.
Keeping up with the curtailment 2025: Beneath the headline numbers
This latest instalment of our annual review into solar and wind farm curtailment across the NEM, looks at outcomes in 2025 and highlights increasingly divergent results by region and by asset as network constraints, pricing dynamics and seasonal weather conditions interact.
Semi-dispatch caps are loading the deviation dice
Following a growing number of articles on WattClarity about “VRE under-performance dragging frequency down”, guest author Allan O'Neil takes a look at how the one sided nature of the SDC plays a role - and suggests a possible action that would help.
How collective under-performance of Semi-Scheduled Solar Farms weakened frequency on Sunday afternoon 30th November 2025
We’ve already posted about how ‘Mainland Frequency dragged downwards around sunset, on Sunday 30th November 2025’. Here, we see how underperformance across Large Solar Farms was a major cause.
Extending the tabulated history of significant (Frequency and/or AggROT) events into 2025 Q3 and 2025 Q4
An update of earlier article (from 8th Sept 2025) comparing Frequency Excursions with instances of large AggROT across Semi-Scheduled units - for 2025 Q3 and 2025 Q4 (ytd).
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 this was another instance of frequency weakness due to Semi-Scheduled unit...
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 urge the Nelson Review panel to (re)consider (with respect to Invisible...
Selected 4-second data relating to the (SemiSched-induced) frequency weakness on Thursday 16th October 2025 (i.e. Part 4)
In Part 4 of this evolving Case Study, we take a closer look (using 4-second data) at the 12 x offending Semi-Scheduled units that appear to have played a large role in driving frequency south on late Thursday afternoon 16th October 2025, outside of the...
Taking a first focused look at the 16:50 dispatch interval on Thursday 16th October 2025 (with frequency dropped below NOFB) … Part 3
In Part 3 of this series with respect to Thursday 16th October 2025, we focus on when a large collective under-performance across all Semi-Scheduled Wind Farms and Solar Farms dragged the frequency outside the NOFB - down at 49.824Hz at 16:49:07.6.
Peeling the second layer of the onion, with respect to the (SemiSched-induced) frequency weakness on Thursday 16th October 2025
Having already noted the ‘Weakness in frequency stability on Thursday afternoon 16th October 2025’, we take a look at the causes - for the four high-profile dispatch intervals.
Trended physical/technical availability of Semi-Scheduled units – aggregated
A zoomed-out view of six metrics supports understanding of physical/technical semi-scheduled generator availability.
3.5 months after the turbine fire at Bulgana Wind Farm, we take an updated look
Combining together a bundle of different metrics related to the 'availability' of a wind farm, we take a look at what's happened at Bulgana Wind Farm over the past ~25 months.
Highlighting particular (frequency and/or AggROT) events through 2024 and 2025
In this article, we tie together various events since 1st January 2024 that featured either System Frequency outside the NOFB and large AggROT for Semi-Scheduled assets.
Peeling the onion a little more – Solar Farm performance on Tuesday 19th August 2025, with the frequency spike to 50.2Hz
As the 5th article in an evolving series that progressively explores the (apparent self-forecasting glitch and) frequency spike on Tuesday 19th August 2025, we take an early look at Solar Farm performance.
An updated tabular list of instances of large AggROT across Semi-Scheduled units
Earlier today we trended the incidence of large Aggregate Raw Off-Target across all Semi-Scheduled units. In this updated tabulated list, we list each of the largest instances from January 2024 to June 2025.
An updated long-range trend of large instances of Aggregate Raw Off-Target (AggROT) across all Semi-Scheduled units
It's ~18 months since we took a look at the trend of large instances of Aggregate Raw Off-Target across all Semi-Scheduled units. In this article we update the analysis with data to 30th June 2025.