This is a question we’ve been asking for many years … such as in Observation 13/22 within GenInsights21.
For those who sit towards either extreme of the Emotion-o-meter, note that this particular question:
1) Is not a function of the inherently variable nature of the underlying energy resource (i.e. the Solar and Wind);
2) Rather, this question
(a) is more focused on some particular aspects of how those units are able to operate, under the rules.
(b) and wonders, for instance, whether the Semi-Scheduled category should be capped, or closed, or curtailed – with (some or all?) VRE units then required to register and operate as fully Scheduled hybrid 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.
The (concerning) frequency spike across the NEM in the middle of the day (Tuesday 19th August 2025) has triggered many proximate questions - understandable - but also has raised these 3 Broader Questions.
Yesterday's release of the draft report of the Nelson Review has prompted me to re-frame a question I've asked before about the Semi-Scheduled category.
Here on this site, and also in real discussions in the offline world, we have been pondering this question for a number of years. For instance, it was pondered in Theme 13 (‘What’s the...