A first look at the frequency performance, with today’s trip at Kogan Creek

We’ve already noted the ‘(Close to) Full Load trip of Kogan Creek early on Thursday 2nd April 2026’.

… from that article the key points were that:

(a)  With Dispatch Interval data, the unit tripped from 722MW (FinalMW at 03:00 NEM time on Thursday 2nd April 2026) to 0MW (FinalMW at 03:05)

(b) A rebid was received at the AEMO at 03:03 NEM time following the trip

So (remembering the building blocks of time) we deduce that the trip occurred sometime between 02:55 and 03:00.

We’ve been writing many articles about frequency disruptions, some using the higher speed readings we’ve established ourselves of the system frequency measured in Brisbane (i.e. reading at 0.1 second cadence).

Utilising these readings, we show firstly a 4-hour span of time centered on the time of the trip this morning:

As noted there:

1)   The lowest point for frequency this morning:

(a)  was down at 49.88Hz

(b)  following a sharp drop (which is to be expected following an instantaneous trip of that size)

(c)  but note that this was still within the Normal Operating Frequency Band

… so I’m presuming that Contingency FCAS responses were not triggered

2)  This was measured at 02:59:54.4 NEM time

… so we deduce that this was the timing of the trip of the KPP_1 unit.

Out of curiosity, we zoomed into a 1-hour time range to see the span of the frequency disruption at a Dispatch Interval level:

With this:

1)  We see that it took ~10 minutes for the frequency to return to within the PFR Deadband;

2)  Which we presume was assisted by a combination of:

(a)  Inertia:

i.  Noting that the level of inertia at this time was higher than at other times

ii.  Not just because it was overnight (so no Large Solar or Rooftop PV);

iii.  But also because the level of Wind output was modest (entirely coincidentally).

(b)  PFR … for the Scheduled and (fewer than hoped for) Semi-Scheduled units providing this

(c)  and Regulation FCAS … for those units enabled to provide this.