Mercury NZ has awarded ANDRITZ a contract to upgrade three hydropower plants – the Maraetai I, Ātiamuri and Ōhakuri stations – in New Zealand.

The project includes the supply of nine new turbines and 13 generators as part of a wider refurbishment programme aimed at improving reliability and increasing generation capacity. The contract, valued in the lower three-digit million-euro range, will be recorded in ANDRITZ’s first-quarter 2026 order intake.

The three plants are part of Mercury’s Waikato Hydro System, which provides approximately 10% of New Zealand’s electricity. Built between the 1950s and 1960s, the facilities will undergo full modernisation including new turbines, generators, governors and associated electromechanical equipment.

Once completed, the upgrade will increase the combined installed capacity of the plants by 76MW, from 376MW currently, and add an estimated 87GW-hours of annual generation. The work is also intended to improve long-term operational reliability.

“Our hydro stations on the Waikato River were constructed from the late 1920s to the 1970s and have worked hard to keep the country powered. We have invested heavily in a long-term refurbishment programme to improve the efficiency and longevity of our hydro stations, to ensure these assets can manage water flow in a way that preserves the environment while optimising power generation,” commented Mercury chief executive Stew Hamilton.

“These ongoing improvements will make a significant contribution to a sustainable energy future for New Zealand. We are pleased to embark on the next step in our refurbishment programme with our trusted partners at ANDRITZ.”

ANDRITZ will handle the design, manufacturing, installation, testing and commissioning of the equipment. Production will take place at the company’s facilities in Austria.

This is the fourth major hydropower contract awarded to ANDRITZ by Mercury, following previous projects at the Karāpiro, Aratiatia and Whakamaru stations. The latest order reinforces ANDRITZ’s position in New Zealand’s hydropower sector.

Mercury generates around 8TW-hours of electricity annually from renewable sources including hydro, geothermal and wind. Its assets account for nearly 20% of New Zealand’s total electricity generation, in a system where renewables already supply between 85% and 90% of demand.