Major battery storage for Huntly Power Station site

Genesis Energy has commenced construction of a 100 MW grid-scale battery at Huntly Power Station, marking a major milestone in New Zealand’s energy storage ambitions.

The project officially broke ground on 5 June, with a ceremony attended by Energy Minister Simon Watts, Electricity Authority chief executive Sarah Gillies, Waikato District Council CEO Craig Hobbs, Genesis CEO Malcolm Johns, and representatives of local iwi.

The battery will offer 200 MWh of storage—enough to power around 60,000 average homes for two hours during winter—and is expected to come online by late 2026. It will provide critical support to the national grid during peak demand periods, especially on cold winter mornings and evenings.

“We’ll be able to store electricity in the battery during times of high generation, and release it when it’s most needed,” said Johns.

Energy Minister Simon Watts said grid-scale batteries are a key enabler of a more secure and affordable energy system.

“By integrating grid-scale batteries, we can reduce energy price volatility, decrease reliance on fossil fuels, and pave the way for a sustainable and resilient energy future,” said Watts.

Broader strategy

The project aligns with Genesis’ broader Gen35 strategy, which aims to decarbonise its generation portfolio. This battery is the first stage in a multi-phase plan to develop up to 400 MW of battery capacity at the Huntly site by FY35.

Johns also highlighted the synergy between battery storage and renewable generation, noting Genesis’ recent launch of its first solar farm in Lauriston, Canterbury.

“We can store the equivalent energy generated by solar farms during the day, and release it at night when customer demand is high,” he said.

French battery specialist Saft will supply the 70 battery units, with Northpower handling installation. The project is expected to come in under its $150 million budget.

The battery will connect directly to the Transpower substation at Huntly, offering strategic access to high-demand centres including Auckland, Hamilton and Tauranga.

“Huntly is evolving,” Johns said. “As New Zealand’s electricity supply becomes more renewable and weather-dependent, this battery will help ensure supply remains reliable and secure.”

Image: Malcolm Johns, Genesis CE, and Energy Minister Simon Watts at the site launch.