Investigations – open for parties to join

There are currently no investigations open for parties to join.

Investigations – closed for parties to join

Investigation of alleged breach by Transpower New Zealand Limited as the grid owner

This investigation concerns the grid owner failing to ensure that it commissioned the protection system for Hamilton transformer T6 (T6) so that the protection system would be selective when operating, so that the minimum amount of assets was disconnected. On 25 January 2018, the differential protection relay operated when it should not have, and unnecessarily tripped T6 resulting in a loss of supply to a widespread area.

Investigation of alleged breaches by Transpower New Zealand Limited as the grid owner

The investigation concerns three separate breaches when the grid owner’s protection settings were not selective during faults so that the minimum amount of assets were electrically disconnected. The assets disconnected were transformers at Invercargill, Bombay and Southbrook grid exit points.

Investigation of alleged breaches by Nova Energy Limited

The investigation concerns Nova Energy Limited changing price instead of offer quantity to reflect unavailability of its McKee generation plant on 23 April 2018.

Investigation of alleged breach by Transpower New Zealand Limited as the grid owner

The investigation concerns the grid owner failing to ensure that it operated the HVDC within the limits of the asset capability statement that it had provided to the system operator. 

Transpower New Zealand Limited as the grid owner

The investigation concerns the grid owner reconnecting two parts of the grid which were not synchronised on 2 March 2017.

Transpower New Zealand Limited as the system operator

The investigation concerns the system operator’s actions when re-establishing normal operation following an event on the grid on 2 March 2017.

Closed investigations

Compliance – Decisions - Investigations closed – no settlement reached

Compliance – Decisions - Investigations closed – settlement reached