Transpower plans to deliver the investments under a staged major capex project. The proposed first stage includes projects:

  1. upgrading the HVDC link between the South Island and the North Island
  2. enhancing the capacity of the Central North Island circuits
  3. enhancing the capacity of the circuits between Wairakei and Whakamaru.


Staging allows Transpower to consult on the long-list of options for the three staging projects above simultaneously. Drawing on feedback from the long-list consultation, Transpower can then test and advance investment options to the short-list consultation for further feedback from interested parties, before submitting its major capex proposal for the first staging project to us. Transpower’s consultation for each subsequent staging project must then reflect the materiality of changes to components of the project since Transpower’s previous consultation on those components.

On 12 August 2021, Transpower agreed with us a consultation programme; an approach to considering non-Transmission solutions; and approximate dates for Transpower to submit to us, and for us to make our decision on Transpower’s major capex proposal for the first stage of the project. As Transpower develops its proposal for the first stage, Transpower will review with us the consultation programme and these dates as necessary.

On 5 December 2022, Transpower submitted their Net Zero Grid Pathways Stage 1 major capex proposal. During our assessment of Transpower’s proposal we identified information that we needed before we could reach a draft decision. Transpower submitted an Addendum – amending their proposal on 13 June 2023. In August 2023, Transpower sought further views from stakeholders following the identification of errors in its modelling. Transpower now prefer a different option to that put forward in its December 2022 application, and also to the option it preferred in its June 2023 Addendum. As a result Transpower undertook a second round of consultation to provide stakeholders with the opportunity to comment on its revisions.

Transpower submitted an updated proposal on 25 September 2023. The Commission published its draft decision on that proposal on 16 November 2023. We completed our consultation on the draft decision on 25 January 2024.

We published our final decision on 28 February 2024.