3 October 2016 under-frequency event

This consultation sought feedback from generators, the grid owner and other participants who may have been substantially affected by an under-frequency event on 3 October 2016 and our draft determination. No submissions on the draft determination were received. Accordingly, the Authority’s final determination under clause 8.61(9) of the Code is that Contact Energy was the causer of the under-frequency event on 3 October 2016.

The Authority’s reasons for this final determination are:

• the interruption/reduction of energy on 3 October 2016 occurred at the Stratford power station, which belongs to Contact Energy
• it has not identified any other asset as having caused or potentially caused this under frequency event
• in the system operator’s view, Contact Energy was the causer of this under-frequency event
• the system operator wrote to Contact Energy (on 18 October 2016) setting out its view that the event was initiated at the Stratford power station resulting in a loss of injection, and seeking any information Contact Energy could provide
• in its reply to the system operator (dated 17 November 2016), Contact Energy has accepted that it was the causer of this event
• having considered the system operator’s report and the relevant elements of the Code, the Authority (based on the information available to it at this time) concurs with the system operator’s findings.

In accordance with clause 8.65 of the Code, the clearing manager will rebate the $338,750 event charge to relevant generators and the HVDC owner.