Energy margin data to be published monthly

The Electricity Authority Te Mana Hiko is introducing a new requirement for electricity generators to provide information.

Under a new information-gathering notice issued under clause 2.16 of the Electricity Industry Participation Code 2010, large generators will be required to provide financial information so we can calculate energy margins on an ongoing basis.

We will publish aggregated, averaged energy margin data on a monthly basis alongside the average weekly spot price to improve transparency, strengthen our monitoring of market outcomes, and support confidence in the wholesale electricity market.

The decision to require generators to provide this information follows a consultation late last year.

Energy margin data helps us better understand what is happening in the wholesale electricity market and how profitable generation is, particularly during periods of high prices. We will use this information alongside our existing monitoring to better understand market outcomes and support our assessment of whether the market is working well.

The notice applies from 5 July 2026 and the first publication will be in September 2026.