Mercury breaks ground on 50-MW Nga Tamariki geothermal power plant expansion

Nga Tamariki 5 geothermal power station groundbreaking ceremony with (L-R) Omer Cohen (Ormat) Scott St John (Chairperson of Mercury), Roger Pikia (Chairperson of Ngati Tahu Ngati Whaoa), Wikitoria Hepi Te Huia (Chairperson of TN2T) (Source: Mercury via LinkedIn)

Power company Mercury, along with representatives from Tauhara No. 2 Trust, Ngati Tahu-Ngati Whaoa Runanga, and Ormat Technologies Inc. participated in a groundbreaking ceremony to signal the start of construction of the 50-MW geothermal power plant at the Nga Tamariki geothermal power station in New Zealand.

This will be the fifth unit in the Nga Tamariki geothermal power station and will boost its capacity by 46 MW. This translates to an output of about 390 GWh per annum, or equivalent to the power supply of an additional 55,000 households. The new power plant is expected to be operational by 2025.

“We’ve worked hard with our partners Tauhara North #2 Trust and the wider mana whenua Ngati Tahu Ngati Whaoa to ensure this expansion considers the long-term sustainability of the whenua (land) while also preserving the cultural significance of this important taonga (treasure),” stated Mercury in their LinkedIn post announcing the event.

The planned expansion was first announced in September 2023 during an investor presentation of Mercury. The expansion will cost NZD 220 million (around USD 130 million, excluding capitalised interest, geothermal drilling of ~NZ$35m and sunk costs of NZ$3m), part of the signalled total commitment of up to NZ$1 billion investment in generation expected in FY24 by Mercury.

“This investment is the first wave of the NZ$1 billion we expect to commit this financial year to generation development we will construct over the next 3 years. It’s another important step in our ambitious programme to bring more renewables online for Aotearoa New Zealand,” said Mercury Chief Executive, Vince Hawksworth in a previous announcement.

Ormat Technologies was selected as the EPC contractor for the project. The new power plant will be built on the same platform as the existing power plant using the Ormat Energy Converter (OEC) technology. The new power plant will utilize Ormat’s advanced state-of-the-art organic Rankine cycle technology and is equipped with the latest turbine providing not only high efficiency and reliability, but also requiring lower maintenance.

This development, once complete, will make the Nga Tamariki facility the largest pure binary power plant in New Zealand and one of the top 5 largest globally.

Source: Mercury via LinkedIn