Geothermal energy is effectively a renewable resource that does not consume any fuel or produce significant emissions. Although some geothermal fields have been degraded, none have ever been exhausted and sustainable development is possible. Geothermal energy also has the advantage over other renewables that it is independent of climatic variation.
Geothermal energy is a relatively low-cost and indigenous generation option that can contribute to New Zealand's growing demand for electricity. It is uniquely reliable, with geothermal power stations typically achieving load factors of 95%, compared to typical load factors of 30 - 50% for hydro and wind power stations. The Wairakei power station has operated at a load factor of more than 90% for over 40 years with low operating costs. This inherent reliability makes geothermal generation a valuable component in a diverse electricity supply system such as New Zealand's.