Last updated: 06 Apr 2023
What we're doing
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.
Our HVDC inter-island link is a key part of New Zealand's National Grid - transporting bulk electricity between the North and South Islands and balancing New Zealand's energy demands. We are at the early stages of an investigation looking to ultimately replace the existing submarine cables of the HVDC link and potentially add further capacity with another submarine cable.
Why we're doing it
Our HVDC submarine cables are nearing the end of their operational life (40 years), and will be due for replacement around 2030. The lead times for ordering and installing new cables are very long hence we are starting now. Any replacement or new cables approved would likely be installed in the late 2020’s and early 2030’s.
More information about the investigation
Transpower signalled this investigation as part of its Net Zero Grid Pathway work.
Because of the relationships between this project, the capacity of the Central North Island transmission network and the capacity of the Wairakei Ring, we are undertaking the investigations concurrently. At the end of 2022, Transpower submitted a proposal for the next stage of investments to the Commerce Commission. For the HVDC, the initial proposal is to install more reactive equipment at Haywards to remove constraints on our existing HVDC capacity. More information is available on the Net Zero Grid Pathways updates page.
Downloads
HVDC Submarine Cables Q&A [ pdf 115.28 KB ]