Frequency change with Yallourn unit 2 trip
We assess whether the trip at Yallourn 2 on 26 August 2025 was large enough to drive a frequency disturbance.
Fast Frequency Response (FFR)
Prices spiking again in South Australia (for Lower 1 second FCAS) on Wednesday 27th August 2025
A very short article with a snapshot from ez2view at the 11:15 dispatch interval – highlighting that Lower 1-second FCAS prices in the South Australian region are spiking (yet again!).
Administered Pricing for FCAS services in South Australia ended on Sunday 24th August 2025 … so what’s next?
On Sunday 24th August 2025, Administered Pricing for FCAS in South Australia ended ... when will the ‘S-TBTU’ constraint set re-emerge?
Part 2 with respect to Administered Pricing for Lower 1 second FCAS (and 9 other services) in South Australia
With Administered Pricing of all 10 x FCAS products in South Australia continuing into Monday 18th August 2025 (no surprise there), we take a second look.
Very fast FCAS, 2024 in review
A 2024 review of the trend in the very fast FCAS services captures enablements, availabilities and costs.
Very fast FCAS markets continue to grow
Six observations from a chart summarising how capacity, availability and volumes enabled have changed over the early phase of the very fast FCAs markets, since commencement on October 9, 2023.
The *other* market change that went live today (Monday 9th October 2023)
A short note about the publication of a richer MT PASA DUID Availability data set in ez2view v9.8 - made possible as a result of the other change that goes live in the NEM...
Very Fast Raise and Lower FCAS markets to start on 9 October 2023
Very Fast FCAS, because it operates at a faster timescale, can arrest the rise or fall in frequency more rapidly than the current fast service and therefore provides an avenue to mitigate the costs...
Enablement of ‘MaxAvail’ in the Bid for Semi-Scheduled units to go live (Mon 7th or Tue 8th Aug 2023) … and other enhancements in future
2 x AEMO Market Notices this afternoon prompt this article about four upcoming Market Enhancements ... with the first to planned to commence from next Monday 7th August 2023
AEMC published Final Rule on Fast Frequency Response (FFR)
A quick note following AEMC publication of final determination on Fast Frequency Response (FFR).
Moving from mandatory PFR to an arrangement that’s more durable
A quick synopsis of some market reforms at the AEMC relating to system frequency.
Observations of differences in system frequency in the Mainland NEM (comparing 2019 to 2021)
One of the many data sets being crunched as part of our analytical efforts underpinning the development of 'GenInsights21' is system frequency. In this short article today, we share some initial observations on how...
FCAS goes from fast to very fast
Just under 3 weeks ago (on 22nd April 2021) the AEMC published a draft determination that would establish 'Fast Frequency Response' as an additional (i.e. 9th and 10th) FCAS service in the NEM. We...
Do you know the difference between Virtual Inertia and Fast Frequency Response?
Our guest author Stephen Sproul looks at how the Dalrymple Battery Energy Storage System (BESS), currently the only source of virtual inertia on the NEM, responded to the November 2019 SA islanding event.
Fast Frequency Service – Treating the symptom not the cause?
The National Electricity Market (NEM) is designed to operate at 50 Hz. Frequency deviation occurs when generation and load are mismatched. It is important in a lightly meshed and long network such as the...