Whilst I am using ez2view, thought it would also be useful to post this snapshot of the ‘Unit Dashboard’ widget in ez2view focused on the KPP_1 DUID (i.e. Kogan Creek power station), to follow last Thursday’s article ‘Industrial Action at Kogan Creek Power station part 2 ’.
This snapshot is for the 11:40 dispatch interval, but looks backwards 2 days (so back into late morning on Monday 25th September 2023, and benefiting from some ‘next day public’ visibility of unit bids and Targets, etc:
On this snapshot I have highlighted two particular time periods…
Time Period #1 … Kogan trips (appears not due to Industrial Action)
We were alerted yesterday (Tuesday 26th September) in the 07:40 dispatch interval when the Kogan Creek unit dropped from 513MW to 0MW (i.e. FinalMW at 07:40) by a pre-configured email alert in the installed ‘Notifications’ widget in the ez2view software.
It looked like a trip at the time … but we could not confirm yesterday …
Why it looked like a trip?
There are several reasons involved…
1) for instance we noted in Part 1 that the short outage (which had moved from last week) was now planned for next week (Mon 2nd, Tue 3rd and Wed 4th October).
2) more generally, units generally don’t come offline from high load if coming down for planned maintenance.
3) plus more, not discussed here.
Why could we not comprehensively confirm?
We could not comprehensively confirm this at the time without the ‘next day public’ data published at 04:00 this morning.
Others also noticed this, including Mike who asked via a comment on this Part 2 Article on Tuesday:
‘Was the trip this morning associated with the strike or is it something else? Nothing in MTPASA from Saturday.’
This was one of the reasons why we thought we’d have more of a look today.
From the bid data (some of which is shown in the image above) we see:
1) Prior to the trip, there were references to ‘Ashing system – SCC –SL’… it’s not immediately apparent to me what the ‘SCC’ acronym represents.
… perhaps this is the reason for the outage planned for next week … but I have not investigated further.
2) For the 07:55 dispatch interval, the availability of the unit was marked down to 0MW with a rebid reason ‘unit commitment – unit trip – SL’ (i.e. the rebid was received at the AEMO at 07:47).
3) The green dotted line on the chart is the ‘PASA Avail’ bid for the unit. We see this did not drop to 0MW until the 23:50 dispatch interval at which point a new rebid reason of ‘unit commitment – unit offline revised – SL’ was submitted (received by AEMO at 23:43
4) The unit was back online with first megawatts for 14:25 (FinalMW = 179MW, shortly prior to volume in the bid).
Time Period #2 … Kogan reduced load (appears not due to Industrial Action)
Comparing its output since coming back online yesterday (~370MW) to the higher low points in output seen on Monday (~500MW) might also raise the question about whether this is due to the noted industrial action (which, after all, did threaten periods of reduced output)?
However, using the ‘bids comparison’ function within the ‘Bids & Offers’ widget inside of ez2view, this lower output seems more likely due to plant physical reasons – with a rebid made at 10:46 on Tuesday 26th September (so taking effect in the 10:55 dispatch interval) being seen to reduce the availability of the unit down to only 320MW following assumed return to service. The rebid reason offered then was:
‘Unit commitment-Unit RTS revised-SL’
… which does not mention anything like industrial action.
So my first sense is that the output is limited more currently by plant physical reasons.
Worth noting that there was a later rebid (not shown here) with rebid reason ‘Boiler -Feed Pump-SL’ which (submitted at 20:46 and taking effect in the 20:55 dispatch interval yesterday) had the effect of increasing (from 21:05) the volume available from the 320MW to the 370MW (i.e. where it is currently operating).
Remember the dashboard to watch in real time
In the part 2 article, we pointed readers to the live-updating dashboard at the following address.
(You should be able to access, if you register an account there)
That article also provided an explanation of what’s displayed…