Why Geothermal?
Geothermal is Renewable
Geothermal systems are renewable sources of energy, harvesting the thermal energy of the earth, through the implementation of appropriate geothermal reservoir management practices.
Every geothermal system is unique and understanding its long-term characteristics ensures that it remains a sustainable and a renewable energy resource for generations to come.
Geothermal is Reliable
Geothermal is the only renewable energy source that is not dependent on the weather and is therefore used as base load energy supply.
Geothermal systems have supplied New Zealand with renewable energy both for power generation and for industrial process heat for over 60 years, with the pioneering geothermal fields continuing strong production at present.
Geothermal is Indigenous
The local expertise and experience are here.
Maori have used and lived with the geothermal resources for centuries. New Zealand engineers pioneered the large scale use of geothermal energy from hot water systems in Kawerau and Wairakei by developing steam-water separators among other pioneering geothermal technologies back in the 1950’s. Up until then, only dry-steam geothermal systems were developed elsewhere in the world.
Geothermal energy is the energy that melts rocks beneath volcanoes and boils rainwater to create geysers, hot springs, and geothermal systems.
The Kawerau Geothermal System was likely formed when the rainwater that seeps deep into the earth is heated by the Puutauaki volcano, forming a hot water reservoir. The hot water upflows near the volcano at temperatures three-times hotter than boiling water, then flows out into seeps and hot springs at Onepuu, Ruruanga, and along the Tarawera River, and also mixes with deep groundwater as it flows into the Rangitaiki plains. The continuous cycle of water recharge and heating creates the renewable geothermal system at present-day Kawerau.
Geothermal energy in the form of hot geothermal water is conveyed to the surface through deep bores. Geothermal water flows up through the bores and starts to boil as it loses pressure. Geothermal steam is separated from geothermal water using locally developed geothermal steam-water separators.
Geothermal energy as process steam and water is available for industrial use and power generation at the steam-water separator pressures and temperatures.