At 15:30 today (Tuesday 23rd September 2025) the AEMO flagged in MN129259 a possible need to intervene in NSW this Thursday 25th September 2025 due to forecast low System Strength as follows:
‘——————————————————————-
MARKET NOTICE
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From : AEMO
To : NEMITWEB1
Creation Date : 23/09/2025 15:30:33
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Notice ID : 129259
Notice Type ID : MARKET INTERVENTION
Notice Type Description : Reserve Contract / Direction / Instruction
Issue Date : 23/09/2025
External Reference : Foreseeable AEMO intervention under clause 4.8.5A (a) of the NER in NSW region
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Reason :
AEMO ELECTRICITY MARKET NOTICE
Foreseeable AEMO intervention under clause 4.8.5A (a) of the NER in NSW region
AEMO has identified a foreseeable circumstance that may require an AEMO intervention event in the NSW region from 0000 hrs 25/09/2025.
The foreseeable circumstance requiring the need for intervention is System Strength.
Manager NEM Real Time Operations
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END OF REPORT
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A quick look at forecasts for NSW coal units via ez2view in the snapshot below reveals a couple of contributing factors:
With respect to the 12 remaining coal-fired units in NSW, there are several points to note:
1) From the ‘Generator Outages’ widget on the left …
(a) we’ve highlighted the MT PASA DUID Availability data for Thursday 25th (which is now ‘stale’ as it has not been updated since Saturday evening 20th September)
(b) from this we can see unit outages flagged at 4 units:
i. Both BW04 and ER04 are on planned outages
ii. Whereas VP5 is on the long-duration unplanned outage due to ‘turbine vibration’ issues noted previously
iii. And we also see an unplanned outage for MP2
> With the unit flagged to come offline this evening
> Noting (though not illustrating here – such as via ‘Forecast Convergence’ widget) that this has been flagged since WHEN
2) In more recent data in the ST PASA data set in the ‘PASA DUID Availability’ widget on the right:
(a) Which was updated with the v9.12 upgrade to cater for the new PDPASA/STPASA data published by AEMO from 31st July 2025;
(b) We also see that ER03 is also now going to have an unplanned outage
i. Beginning in the early hours of Thursday 25th September 2025
ii. For reasons that are not explored here, but presumably to do with the reason why the unit’s only running part-load at present.
PS1 AEMO now (also) flags forecast LOR1 for NSW on Thursday 25th September 2025
No sooner had we hit publish on the article that we note AEMO MN129258 as follows:
‘——————————————————————-
MARKET NOTICE
——————————————————————-
From : AEMO
To : NEMITWEB1
Creation Date : 23/09/2025 16:00:26
——————————————————————-
Notice ID : 129258
Notice Type ID : RESERVE NOTICE
Notice Type Description : LRC/LOR1/LOR2/LOR3
Issue Date : 23/09/2025
External Reference : STPASA – Forecast Lack Of Reserve Level 1 (LOR1) in the NSW Region on 25/09/2025
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Reason :
AEMO ELECTRICITY MARKET NOTICE
AEMO declares a Forecast LOR1 condition under clause 4.8.4(b) of the National Electricity Rules for the NSW region for the following period:
From 1730 hrs to 2300 hrs 25/09/2025.
The forecast capacity reserve requirement is 1431 MW.
The minimum capacity reserve available is 1099 MW.
AEMO Operations
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END OF REPORT
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PS2 AEMO cancels note about possible intervention
At 16:54 the AEMO published MN129261 as follows:
‘——————————————————————-
MARKET NOTICE
——————————————————————-
From : AEMO
To : NEMITWEB1
Creation Date : 23/09/2025 16:54:44
——————————————————————-
Notice ID : 129261
Notice Type ID : MARKET INTERVENTION
Notice Type Description : Reserve Contract / Direction / Instruction
Issue Date : 23/09/2025
External Reference : Cancellation – Foreseeable intervention to manage system strength in NSW region 23/09/2025
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Reason :
AEMO ELECTRICITY MARKET NOTICE
Cancellation – Foreseeable intervention to manage system strength in NSW region 23/09/2025
Refer Market Notice 129259
AEMO no longer foresees a possible requirement for intervention to manage system strength in NSW region. The advice of possible intervention is cancelled from 1645 hrs 23/09/2025.
Manager NEM Real Time Operations
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END OF REPORT
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I’ve not looked to see what changed to trigger this change in outlook but presume that some participant changed their plans (which, indeed, was the purpose of the notice).
PS3 it’s back!
At 11:29 on Wednesday 24th September the warning was reinstated:
‘——————————————————————-
MARKET NOTICE
——————————————————————-
From : AEMO
To : NEMITWEB1
Creation Date : 24/09/2025 11:29:35
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Notice ID : 129276
Notice Type ID : MARKET INTERVENTION
Notice Type Description : Reserve Contract / Direction / Instruction
Issue Date : 24/09/2025
External Reference : Foreseeable AEMO intervention under clause 4.8.5A (a) of the NER in NSW region
——————————————————————-
Reason :
AEMO ELECTRICITY MARKET NOTICE
Foreseeable AEMO intervention under clause 4.8.5A (a) of the NER in NSW region
AEMO has identified a foreseeable circumstance that may require an AEMO intervention event in the NSW region from 0130 hrs 25/09/2025.
The foreseeable circumstance requiring the need for intervention is System Strength.
Manager NEM Real Time Operations
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END OF REPORT
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I’ve similarly not looked at what changed this time
PS4 possible early morning direction overnight
We’ve called out MN129729 published on at 14:29 in the article ‘AEMO notes possible early-morning intervention in NSW on Thursday 25th September 2025’.
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