TPM technical amendments: regulatory asset base indexation and simple method benefit-based charge cap
Consultation
We are seeking feedback on two proposed technical amendments to the transmission pricing methodology (TPM).
We propose:
- Aligning the transmission pricing methodology with recent Commerce Commission changes to index Transpower’s regulatory asset base. This would ensure the approach to valuation and depreciation of assets in the TPM is consistent with the Commission’s approach.
- Clarifying the simple method benefit-based charges cap formula so it always uses the same customer allocations that applied at the start of the relevant (five-year) simple method period. This would ensure the result of the cap calculation is the same regardless of when the adjustment occurs within the five-year period.
These proposed changes help ensure the transmission pricing methodology continues to function as intended.
A well-functioning TPM supports timely, well-placed investment and use of the grid, and the electrification of the economy for the benefit of all New Zealanders.
We welcome your feedback on these proposals by 5pm, Friday 29 August 2025.
Make a submission
Our preference is to receive submissions to the questions in Appendix B to our Information Provision Platform at https://info.ea.govt.nz/sl/76125a
If you can’t send your submission electronically or would prefer to send a Microsoft Word submission, please contact network.pricing@ea.govt.nz or 04 460 8860 to discuss.
We will publish all submissions. If you consider that we shouldn’t publish any part of your submission, please:
- indicate which part should not be published and explain why
- provide a version that we can publish (if we agree not to publish your full submission).
All submissions, including any parts the Authority doesn’t publish, can be requested under the Official Information Act 1982.