The Tauhara power project is a 168MW geothermal power plant under construction in the North Island of New Zealand.
Contact Energy, an electricity and gas utility based in New Zealand, is developing the project with an estimated investment of NZ$818m ($547m).
Construction works on the project commenced in early 2021, with the first power from the geothermal facility expected by the second half of 2023.
At full capacity, the Tauhara geothermal power station is estimated to produce 1,4 terawatt-hours (TWh) of electricity and offset 500,000 tonnes (t) of carbon dioxide (CO2) emissions a year.
Location and site details
The geothermal power station is being built on the Tauhara geothermal field located near Lake Taupo within the Taupo Volcanic Zone in central North Island, New Zealand.
The project site lies off the Broadlands Road east of the Taupo township, 280km south of Auckland.
Tauhara geothermal power development details
Tauhara will be the sixth geothermal power plant to be operated by Contact Energy in New Zealand’s central North Island region.
The company’s five existing geothermal facilities in the region include the 28MW Te Huka, 44MW Ohaaki, 55MW Poihipi, 132MW Wairakei, and the 166MW Te Mihi power plants.
Contact Energy received consent to develop up to 250MW of geothermal power generation capacity at Tauhara in 2010. The project, however, remained in planning stage for more than ten years due to low electricity demand in the region.
The company took final investment decision (FID) to build a 152MW geothermal power plant at Tauhara in February 2021, after completing the drilling of four geothermal appraisal wells at the site in June 2020 with an estimated investment of NZ$40m ($26m).
With the Tauhara geothermal reservoir productivity considered to be higher than initially anticipated, Contact Energy revised the estimated power output of the project from 152MW to 168MW in February 2022.
Tauhara geothermal power plant make-up
The Tauhara geothermal power plant will be equipped with a single-shaft steam turbine and generator unit supplied by Fuji Electric to produce 168MW of electricity.
It is expected to be the world’s biggest single-turbine geothermal power unit after the 140MW Nga Awa Purua geothermal power station in Waikato, New Zealand.
The power station will also feature a fibreglass reinforced plastic (FRP) induced draft cooling tower along with associated infrastructure at the site.
The electricity generated by the Tauhara geothermal power station will be evacuated into New Zeland’s National Grid operated by state-owned Transpower.
The plant’s power output will be supplied to Unison’s electricity distribution network in Hawke’s Bay, Taupo and Rotoru.
Power purchase agreement
Genesis Energy signed a long-term power purchase agreement (PPA) with Contact Energy in August 2021 to offtake 62.5MW of electricity from the Tauhara geothermal power plant for a period of 15 years starting from January 2025.
Sumitomo Corporation was awarded an engineering, procurement and construction (EPC) contract for the Tauhara geothermal power plant in February 2021. It also secured an early works contract for the project in June 2020.
Fuji Electric, an electric equipment company based in Japan, was subcontracted by Sumitomo Corporation to manufacture and supply the steam turbine and generator for the geothermal power plant in February 2021.
Naylor Love, a construction company based in New Zealand, was selected as the balance of plant (BoP) EPC contractor for the project.
Hamon Group was subcontracted to manufacture and supply the FRP induced draft cooling tower for the geothermal power plant in August 2021.
Jacobs was engaged to provide the steam field design, whereas MB Century was hired to drill the geothermal wells at the site.
Hicks Bros was contracted for the site earthworks, whereas Seay Earthmovers and Cheal Consultants were engaged for the associated earthworks to develop the turbine and generator hall area.
Connell Construction, Delta Contractors and Reofab were engaged to perform civil works related to the cooling tower basin and the turbine hall pedestal foundation.
Thermakraft provided 130 rolls of 300-micron Thermathene Orange high-strength concrete underlay for the cooling tower basin slab, whereas Taupo ITM, CARTERS Napier, and Hastings supplied the remaining rolls.
Allied Concrete and Firth Industries were contracted to supply concrete for the plant construction.