About the TPM

The Electricity Authority's transmission pricing methodology (TPM) determines how Transpower recovers the annual cost of running the national transmission grid from transmission customers.

Introduction

The current TPM has applied since 1 April 2023.

Under the TPM, transmission charges are allocated to Transpower's customers via a benefit-based system. In a benefit-based system, those that are expected to benefit most from the current and future investment pay the costs. The TPM has been designed to reflect the costs and expected benefits of electricity transported across Transpower's 12,000 kilometres of transmission lines.

The TPM is available on the Authority's website

Useful documents

To help people understand the TPM we have prepared the following resources. Over time we will develop and share more information about how the TPM works in practice.

Document Download
Guide to the TPM v3 View
Information sheet on treatment of new customers View
Information sheet on treatment of battery storage View
Information sheet on embedded generation View
Information sheet on disconnecting from the grid View
Information sheet on connection charges v3 View
Information sheet on connection charges: FAC mechanism to address Type 1 FMD v3 View
Information sheet on connection charges: Anticipatory investment and Type 2 FMD v3 View
Information sheet on residual charges v4 View
Information sheet on benefit-based charges: Simple method v3 View
Information sheet on benefit-based charges: Standard methods v2 View
Information sheet on benefit-based charges: Appendix A BBIs v2 View
Information sheet on benefit-based charges: Adjustments v3 View
Information sheet on benefit-based charges: Covered cost v2 View
Information sheet on transitional price cap v2 View
Information sheet on prudent discounts v2 View
Prudent discount manual View
Information sheet on reassignment View
Reassignment practice manual  View

TPM Newsletters

Here you will find updates related to our work implementing the TPM, including information about engagement opportunities and consultations.

2025

6 June 2025: Refresh of our website content

2 May 2025: TPM post-implementation survey

2024

 

25 November 2024: Assumptions Book 2.0 now available

30 October 2024: No submissions received for Assumptions Books 2.0 consultation

7 October 2024: Consultation on assumptions book update

7 August 2024: Updates to Grid Pricing website information

17 May 2024: TMP update - adjustment events

23 April 2024: SRAM cost recovery update

2023

 

16 November 2023: Decision documents published for WUNIVM1b OTA STATCOM BBI consultation

02 October 2023: No submissions received for WUNIVM1b OTA STATCOM BBI consultation

26 September 2023: TPM - OTA STATCOM consultation closes on Friday 29 September 2023

07 September 2023: Net Zero Grid Pricing phase one BBI consultation closes

31 August 2023: TPM updated consultation schedule - three open consultations 

23 August 2023: TPM consultation on NZGP benefit-based investments - submissions due 6 September 2023

28 June 2023: Decision documents for HVDC Pole 2 refurbishment and WUNIVM1a BBI customer allocation consultations published

02 June 2023: Extension for NZGP phase 1 starting BBI customer allocations consultation

17 May 2023: New Settlement Residue Allocation Methodology (SRAM) published & NZGP BBI consultation reminder

27 April 2023: TPM BBI consultation for two components of NZGP phase one MCP proposal

01 April 2023: TPM decision published

24 March 2023: TPM HVDC Pole 2 consultation closed

16 March 2023: TPM BBC Assumptions Book v1.1 published

10 March 2023: TPM submission received on HVDC Pole 2 refurbishment BBI consultation and new FAQs

07 March 2023: TPM assumptions book consultation - no submissions received

01 March 2023: TPM assumptions book consultation submissions due next Monday and new BBC FAQ

15 February 2023: TPM consultations submission date extensions due to Cyclone Gabrielle and new SRAM FAQ published

10 February 2023: TPM consultation update - WUNIVM Stage 1a BBI and Assumptions Book update

01 February 2023: New TPM consultation package, a decision, and new resources published

19 January 2023: TPM consultation on proposing starting allocations for HVDC Pole 2 refurbishment

2022

 

22 December 2022: Meri Kirihimete (Merry Christmas) from the Transpower Grid Pricing team

16 December 2022: Minor change to WUNIVM Stage 1a consultation paper

15 December 2022: TPM consultation on proposed starting allocations for WUNIVM Stage 1a

07 December 2022: Electricity transmission charges from April 2023

01 December 2022: TPM consultation cross-submissions published

23 November 2022: TPM submission and new information sheet published

15 November 2022: TPM consultation reminder and new information published

09 November 2022: TPM consultation on draft prudent discount and reassignment manuals and new information sheet published

29 September 2022: TPM new information sheets and questions published

15 September 2022: TPM decisions published for four consultations and new consultation schedule available

25 August 2022: TPM indicative pricing update and new residual charges information sheet

18 August 2022: TPM connection asset replacement costs consultation cross-submissions published

12 August 2022: TPM connection asset replacement costs consultation late submission published

11 August 2022: TPM connection asset replacement costs consultation submissions published

28 July 2022: TPM consultation on connection asset replacement costs

21 July 2022: Webinar rescheduled - NZGP indicative pricing for shortlist consultation

14 July 2022: TPM cross-submission published for consultation on reclassification of Buller region assets

07 July 2022: TPM submission published for consultation on reclassification of Buller region assets

23 June 2022: TPM consultation on reclassification of Buller region assets

21 June 2022: TPM consultation cross-submissions published on proposing starting benefit-based investment customer allocations for CUWLP

16 June 2022: TPM re-submission by ENA on CUWLP benefit-based investment consultation published

14 June 2022: TPM submissions on CUWLP benefit-based investment consultation published

07 June 2022: TPM draft assumptions book cross-submissions published

01 June 2022: TPM reminder on draft assumptions book and CUWLP allocation submission dates

27 May 2022: TPM submissions on our draft assumptions book published

17 May 2022: TPM CUWLP BBI consultation

04 May 2022: TPM online drop-in session reminder: Friday 6 May 1:30pm

29 April 2022: TPM Assumptions Book Consultation

12 April 2022: Transpower to implement a new TPM

 

Questions?

Please email [email protected] if you have any questions about the implementation of the TPM. 

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