Most high temperature geothermal resources produce a mixture of water and steam at temperatures up to 300ºC. A few resources, or more often limited sectors within a large system, produce dry steam. The energy accessed can be used to generate electricity in geothermal power plants or used directly for a range of purposes. Commercial geothermal energy operations access geothermal fluids by drilling wells typically 1000 to 3000m deep, while domestic wells for heating are usually only around 100m deep. When hot water above 90 to 100ºC flows up the well, the release of pressure allows some of the fluid to boil into steam, resulting in two-phase mixture at the surface. The water and steam are physically separated before use.
Electricity Generation in New Zealand is the main use of geothermal energy. Geothermal energy can provide a significant part of New Zealand’s future renewable energy needs , in both direct use and electricity generation. Click here to see more on Development Potential