Heat stored in the earth is extracted to create geothermal power.
Geothermal power contributes approximately 7% of Aotearoa’s total electricity. Significant areas of geothermal activity are found in the Taupō volcanic zone and in Northland. To generate electricity, high-pressure geothermal hot water is separated into steam and water, and the dry steam is then used to spin the turbines that generate power. Extracting geothermal fluids for power generation is considered relatively environmentally friendly. However, this does not mean that geothermal power generation is without environmental effects.
Geothermal fluids often contain considerable quantities of chemical contaminants such as mercury (Hg) and in some locations these fluids are a significant source of contamination to the natural environment. Geothermal springs can also produce high levels of arsenic and boron. Because of the heat, thermal waters generally support unique biological systems, but often have low invertebrate and mahinga kai diversity.