Seeking feedback on 26 July 2024 under-frequency event

We are seeking feedback from generators, the grid owner and other participants who may have been substantially affected by the under-frequency event of 26 July 2024.

An under-frequency event occurs when the frequency falls below 49.25Hz because of a loss of injection of more than 60MW into the grid. In the case of this event, 231MW of generation injection was lost at the Clyde grid connection point, resulting in a drop of frequency to 49.14Hz in the South Island.

The Authority’s draft determination is that Transpower New Zealand Ltd as grid owner was the causer. The reasons for this are outlined in the draft determination paper.

The Authority is required by the Electricity Industry Participation Code to consult on its draft determinations. All submissions will be considered before our determination is finalised.

We welcome your feedback to compliance@ea.govt.nz by 5pm, 13 May 2025.

View consultation: 26 July 2024 under-frequency event