The Geothermal Heating System at Taupo Hospital, New Zealand

Abstract

Taupo Township is located in the centre of Taupo Volcanic Zone (TVZ), in the centre north island of New Zealand, which has an abundance of natural geothermal resources. The Taupo Hospital sits in the south-east of the township, in the outflow margin of the Wairakei-Tauhara geothermal systems. The direct-use of geothermal energy in the hospital was commissioned in August 2010 to provide space heating and domestic hot water supplies. Previously, coal fired boilers that consumed around 340 tonnes/year of coal were used. By converting to geothermal energy, significant savings were made in terms of fuel and maintenance costs. Geothermal fluid production fluctuates depends on the season. Minimum production is during summer, being 59 tonnes/day and maximum production is during winter, being 279 tonnes/day. The geothermal and heat exchange system has now been running for more than three years and there has been good performance, with no issues pertaining to scaling and corrosion. This is due to a combination of good maintenance practices and the favourable chemical composition of the geothermal fluid.