Waikato and Upper North Island Voltage Management Investigation

Region Map
Auckland population
1.5 M
...and increasing
Improved voltage support by
to meet Auckland's growing demand

We need to continually operate, maintain and develop New Zealand's transmission network - the National Grid - to ensure we meet the ongoing electricity needs of New Zealanders.

A need to investigate

Recent and planned decommissioning of thermal generation plant at Otahuhu, Southdown and Huntly, and demand growth in Auckland, are expected to lead to voltage management issues in Waikato and the Upper North Island, including Auckland.  Efficient voltage management is essential to the reliable delivery of power.

What are the potential solutions

There are many ways of supporting voltage including not only devices such as capacitors, synchronous condensers, statcoms and SVCs, but potentially also demand response and generation solutions.  Moreover, the issue is complex.  A portfolio of different assets – at various locations and commissioned at different times – rather than a single asset solution may well be required. 

The impact of the ‘thermal decommisionings’ has been studied in depth by Transpower.  Genesis has since deferred its Huntly plant retirement from 2018 to 2022 (see Transpower's media release).  Although this provides welcome breathing space, given the lead time for new transmission equipment we need to start investigating the long-term solution now.