1 March 2022 under-frequency event

The system operator recommends that the causer of the 1 March 2022 under‑frequency event (UFE) was Genesis Energy Limited as the generator that owns Huntly Unit 2. Our draft determinations agree with the system operator’s recommendations.

We did not receive any submissions on the draft determination for the 1 March 2022 UFE.

Our final determination, under clause 8.61 of the Code, is that Genesis was the causer of the under-frequency event on 1 March 2022 at 2:57 pm.

Our reasons for this final determination are:

• a UFE occurred on 1 March 2022 at 2:57 pm when the frequency fell to 49.20 Hz in the North Island,
• the interruption/reduction of electricity occurred when unit 2 tripped at the Huntly power station,
• no other asset was identified as having caused or potentially caused the UFE, and
• the system operator and Genesis agree that Genesis was the causer of the UFE.

In accordance with clause 8.65 of the Code, the clearing manager will rebate the event charge to relevant participants. The charge advised in the system operator's report to the Electricity Authority is $200,275.