We’ve already written 3 articles about the earlier-than-expected start to the long (mostly) planned outage of Loy Yang A1 early in the morning of Monday 7th September 2026. In this article (part 4 in the series) we take a first look at widespread voltage fluctuations.
In this article we take the AEMO’s 4-second data and present this trace to start a broader sweep of system effects:, starting with System Frequency following trip of Loy Yang A1 near 4am on Monday 7th September 2026.
Earlier, we noted ‘Unit trip at Loy Yang A1 on Monday morning 7th September 2026 (part 1)’. Here we follow that on with two more snapshots from ez2view to look at the outage in a little more depth.
With the benefit of ‘next day public’ data in ez2view, we can see the 6 x Loy Yang units across Loy Yang A (AGL) and Loy Yang B (Alinta) rebid with some form of ‘coal shortfall’ or ‘coal conservation’ reason.
Another contributor to the high prices in VIC (and TAS and SA) on Wednesday evening 8th July 2026 will be the lower-than-expected output from all 6 x Loy Yang units for unknown reasons. Perhaps some coal issue?
At 09:06 (NEM time) this ‘Notifications’ widget alert from ez2view flags Loy Yang A4 coming offline ... which helps explain the directions for System Strength.
On Saturday evening 30th August 2025 there was a trip (and then subsequent recovery) of the Loy Yang A1 unit - we take a look at frequency change.
In July 2025 AEMO released the final report into the review of the major power system event of 13 February 2024.
The volatility of Thursday evening 12th June 2025 had ended by that time (though not by much), but it’s worth noting that the Loy Yang A1 unit commenced its return to service journey last night.
We’d seen Bayswater unit 2 come offline this morning, and wondered if we'd not seen the unit bouncing ON-OFF a few times recently.
We’ve only just published ‘AEMO directs 4 units on in Victoria, to cover System Strength shortfall’ … noting that, at that time, there were 3 coal units in Victoria offline. Our ‘Notifications’ widget in ez2view has alerted us that Loy Yang A2 unit has also...
Another 'interesting' event today ... a dip in mainland frequency with trip of Loy Yang A2.
A quick record of the trip of Loy Yang A1 unit just prior to 08:40 (NEM time) this morning … Friday 11th October 2024:
For several reasons (including as prompted by conversations with several different clients in recent days) here's a review of rebidding at Loy Yang A1 as the unit came offline on Tuesday 20th August 2024.
A brief follow-on to yesterday evening's article about the unplanned outage at Loy Yang A1 (Tue 20th Aug 2024).
A quick look at some market data in ez2view, with respect to Loy Yang A1 unit coming offline on Tuesday afternoon 20th August 2024.
A brief follow on article about Loy Yang A station, following the A4 unit trip yesterday, and unsuccessful return to service today.
A short record of a coal unit trip around the time of a system frequency drop. on Wednesday 14th August 2024.
A slightly longer summary (compared to this morning's) of some evening volatility (across the NEM) on Monday evening 5th August 2024.
Curiosity (part triggered by some conversations I noticed on social media) drove me to have a look at the implied ROCDOWN in the AEMO 4-second data for the 5 facilities (10 DUIDs) involved in rapid ramp down on Tuesday 13th February 2024.