Grid Pricing

For all the information you need on our revenue, pricing data, rental information, and the TPM.

Grid pricing information

The way Transpower recovers its revenue from its customers (generators, local lines companies, and consumers directly connected to the national grid) is set out in the Electricity Authority’s Transmission Pricing Methodology (TPM), which is in Schedule 12.4 of the Electricity Industry Participation Code 2010. 

Transpower charges each transmission customer a fixed amount each year, which is paid in monthly instalments.

The Commerce Commission determines the total revenue Transpower, as the owner operator of the national grid, can recover each year through transmission charges.  

Useful information:

You can find our current grid charges here

A new TPM from 2023

On 12 April 2022, the Electricity Authority announced its decision to adopt a new TPM, which took effect from 1 April 2023. Total transmission charges remained the same, but how these charges are distributed among transmission customers changed.

The main change in the new transmission pricing methodology was a move to a benefit-based approach where customers pay in proportion to the benefit they are expected to receive from some historic and all future transmission investments. The previous methodology spread the cost of the HVDC link connecting the two main islands across South Island generators and spread the cost of all other interconnection assets across local lines companies and major industrial users.

Read our one-page overview of the TPM here. You can also read more about the new TPM and our work to implement it on our Transmission Pricing Methodology pages. You can find our historical grid pricing information here.

For information on rentals and the Settlement Residue Allocation Methodology (SRAM), click here