Decision confirmed on 17 September 2024 under-frequency event

We recently consulted with the sector on the draft determination of causer for an under-frequency event on 17 September 2024.

An under-frequency event occurred at 2.04pm on 17 September 2024 when Huntly Unit 5 tripped and frequency dropped to 49.16Hz in the North Island.

We had no feedback from other industry participants. We received feedback from one non-industry participant, which mainly related to other issues.

The final determination for this event is confirmed. Genesis Energy Limited (Genesis), as the generator that owns Huntly Unit 5, was the causer of the 17 September 2024 under-frequency event.

In accordance with clause 8.65 of the Electricity Industry Participant Code, the clearing manager will rebate the event charges to the relevant participants. The event charge calculated in the system operator’s report to the Authority is $224,040.41.

Any dispute of this final determination can be lodged with the Rulings Panel by 5pm, 24 April 2025.

About the 17 September under-frequency event