The 100-MW Ngatamariki Geothermal Power Station: A Purpose-built Plant for High Temperature, High Enthalpy Resource

Abstract

Successfully and sustainably tapping high temperature geothermal reservoirs at around 300 ºC at 3000 meters below the ground, requires a very special expertise: a delicate blend of precision multi- disciplinary engineering, mastering technological manufacturing and a dedicated field-proven geothermal experience and knowhow. Some authors have suggested over the years that pure binary systems have a low-efficiency conversion rate and are best suited in the utilization of boiling low-temperature reservoirs. In contrast to those suggestions, several medium-sized geothermal power stations such as the 30-MW Te Huka, 36-MW Rotokawa, 12-MW Kawerau KA 24, and the 30-MW Ngawha are well established examples of high-temperature binary systems operating successfully and sustainably in New Zealand.