Frequency drop on Thursday evening 11th Sept 2025 with Tallawarra B trip
A quick article to explore a frequency drop on Thursday evening 11th September 2025.
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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.
Will I see you at the inaugural ‘NEMdev’ conference in Brisbane on Tue 7th and Wed 8th October 2025?
Worth a short note to point readers here to the current details about the conference – which is to be held in Brisbane on Tuesday 7th and Wednesday...
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...
The new ‘V_NWVIC_GFT1_750’ constraint equation binds, on Wednesday evening 10th September 2025
A short article to look at the first instance of the new ‘V_NWVIC_GFT1_750’ constraint equation binding - on Wednesday evening 10th September 2025 (not 36 hours after it...
Newport Power Station running, with Yallourn’s yips yielding 1 unit operations
We noticed Bruce Mountain’s comments on LinkedIn about Newport power station running overnight, so had a look in ez2view.
Noting the NERC Alert ‘Large Load Interconnection, Study, Commissioning, and Operations’
A quick note to call attention to this recent alert from NERC with respect to ‘Large Load Interconnection, Study, Commissioning, and Operations’
Wobbles at Yallourn unit 4
A brief look at recent operational challenges at Yallourn unit 4.
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.
Outage at Vales Point unit 5 extended – return to service now not expected until 15th December 2025
Subsequent to earlier article about VP5, the expected duration of the outage pushed out by more than a month.
AEMO notes ‘New Victorian system normal constraint to manage contingency size on north-west Victoria’
The AEMO notifies that the new 'V_NWVIC_GFT1_750' constraint equation will first be invoked from 10L00 on Tuesday 9th September 2025.
Vales Point unit 5 (partly unplanned) outage – return to service currently expected 9th November 2025
On Tuesday 26th August 2025 the VP5 unit came offline, with rebid reasons suggesting that ‘turbine vibrations’ were a factor. We take a look ~10 days later.
Daily NOFB exceedances since 2021
We count the number of days each month when there was at least one 4-second measurement outside the NOFB.
AEMC releases July 2024 working paper ‘Addressing the risk of algorithmic collusion’
Today we were alerted that the AEMC had belatedly published this 15-page Staff Working Paper titled ‘Addressing the risk of algorithmic collusion’.
AEMO initiates new operational requirements in SA (1 synchronous unit, in certain circumstances) and NSW (system strength)
Worth a short note today (Wednesday 3rd September 2025) to record AEMO’s Market Notice 128912 published at 16:10
Instances of system frequency outside the normal operating band
How common is it that mainland frequency deviates outside the NOFB (normal operating frequency band)?
(Two not one!) more media article (and 5, not 4, analysts) questioning Eraring’s mooted closure in 2027 … and same for other coal units
It was no surprise at all to open the AFR and see 4 different analysts quoted in voicing their concerns about the unrealistic notion that Eraring can close...
Yes, Tamar Valley CCGT did switch off last week (on Wednesday 27th August 2025)
Looking back to Wednesday 27th August 2025, when Tamar Valley CCGT switched off.
Looking more at (commissioning) operations at Waratah BESS through August 2025
In this article we take a look at operations of Waratah BESS through August 2025 - including some large Dispatch Errors on several days: (a) including Fri 29th...
More about that decay of mainland frequency at lunchtime on Friday 29th August 2025 (i.e. Part 2)
Taking a second look at the midday decay of mainland frequency on Friday 29th August 2025.