Contact Energy considering retirement of original Wairakei geothermal plant
Map with the geothermal plants at Wairakei, NZ (source: Contact Energy)
Alexander Richter
17 Mar 2022
Contact Energy is planning the retirement of its initial Wairakei geothermal power station, yet expand capacity from the field with new plant near the Te Mihi station.
As part of its activities and projects, NZ energy utility Contact Energy is proposing to close the Wairakei A&B geothermal power plants no later than 30 June 2031 according to its GeoFuture strategic initiative.
The company is renewing the resource consents that support its geothermal power stations on the Wairakei geothermal field. The current consents expire in 2026, and Contact is preparing to modernise the way we generate power on the Wairakei field for the next 35 years. The company says it has spent many months working with key stakeholders in advance of applying for new consents. While not completely clear, it seems that the application was lodged late in 2021.
As part of the plans, the company proposes to:
- Close Wairakei A&B Power Stations no later than 30 June 2031.
- Stop all discharges of separated geothermal water from electricity generation into the Waikato River and associated streams no later than 30 June 2026.
- Build a new up to 180 MW development at Te Mihi with an option for a small development at Wairakei.
- Invest significantly in the local Taupo and regional economy with the proposed new development at Te Mihi estimated to cost up to $750m with a significant portion spent in the region.
- Increase generation of renewable, reliable, low-carbon electricity (from about 320 MW to up to 400 MW – enough for 70,000 more homes).
At the geothermal field of Wairakei, Contact Energy has four geothermal power plants, the Wairakei A and B stations with a combined power generation capacity of 125 MW in operation since 1958 (we reported on the 60 years of power generation), the Binary station of 15 MW added in 2005, the Poihipi geothermal plant with 50 MW added in 1997 and the Te Mihi geothermal power plant of 166 MW that started operations in 2014.
The plan is to build a new geothermal power plant (THI B) adjacent to the existing 166 MW Te Mihi plant, which would look like a larger version of the current Wairakei binary plant. This plan would see the increase of output from today around 320 MW to 400 MW. The company has then the further option of building a smaller 40 MW station next to where the current Wairakei A and B stations are.
For sustainability, Contact Energy is seeking to only increase the geothermal take from the field from around 245,000 tonnes per day to 250,000.
Source: Contact Energy
