Electricity distribution input methodologies
This page was updated7 months ago
Input methodologies are the rules, requirements and processes that underpin regulation under Part 4 of the Commerce Act.
We must apply the IMs when we set price-quality paths and set information disclosure requirements. Regulated businesses are also required to apply the input methodologies.
The IMs cover matters like how assets are to be valued, depreciated and revalued, how we estimate the cost of capital, how tax should be treated, and how common costs should be allocated where businesses provide both regulated and unregulated services.
The IMs also set out certain process requirements, as well as the rules relating to electricity distribution businesses applying for customised price-quality paths.
The purpose of IMs is to promote certainty for suppliers and consumers in relation to the rules, processes and requirements for regulation.
The IMs for electricity distribution businesses were originally determined in 2010 and there have been amendments made to the IMs since then.
We are required to review the IMs at least every 7 years. We substantially completed our first review of the IMs in 2016. We completed the second review on 13 December 2023. You can find more information about both reviews below.
The reasons for the IMs for electricity distribution businesses are captured in the reasons papers for the original IM determination and all subsequent amendment determinations – certain determinations and reasons papers can be found via the links below.
2023 input methodologies review
We completed the second review of the IMs on 13 December 2023.
2016 input methodologies review
We substantially completed the first review of the IMs in 2016.
Other past amendments and clarifications
These are certain past decisions we have made related to input methodologies for electricity distribution businesses, and the process of how we got to these decisions.
Current input methodologies for electricity distribution businesses
The consolidated determination below includes the input methodologies that apply for information disclosure regulation, Electricity Distribution Services Default Price-Quality Path Determination 2020 [2019] NZCC 21, and Aurora Energy Limited Electricity Distribution Customised Price-Quality Path Determination 2021 [2021] NZCC 3.
The consolidated determination below does not include the amendments to the input methodologies in “Electricity Distribution Services Input Methodologies (IM Review 2023) Amendment Determination 2023 [2023] NZCC 35” (Amendment Determination 2023) that apply for:
- information disclosure regulation from the commencement of disclosure year 2026;
- a default price-quality path which commences on or after 1 April 2025; and
- a customised price-quality path application made on or after 14 December 2023, and any customised price-quality path resulting from that application.
Interested persons should use the Amendment Determination 2023 below to identify the input methodologies that apply for:
- information disclosure regulation from the commencement of disclosure year 2026;
- a default price-quality path which commences on or after 1 April 2025; and
- a customised price-quality path application made on or after 14 December 2023, and any customised price-quality path resulting from that application.