Survey of Energy Resources 2007
Geothermal Country Notes
Switzerland's installed capacity for utilising geothermal energy has grown rapidly in recent years and the country now ranks among the world leaders in direct-use applications (there is no geothermal-based electricity). There are two main components to Switzerland's geothermal energy: the utilisation of shallow resources by the use of horizontal coils, borehole heat exchangers (BHE), foundation piles and groundwater wells, and the utilisation of deep resources by the use of deep BHEs, aquifers by singlet or doublet systems, and tunnel waters. In virtually all instances heat pumps are the key components.
In 2005 there were over 35 000 ground-source heat pumps installed throughout the country, representing about 532.4 MWt. The remaining 49.2 MWt of capacity was utilised for bathing and swimming (40.8 MWt), district heating (6.1 MWt), air conditioning (2.2 MWt) and snow melting (0.1 MWt).
Research had shown that the area of Basle in northern Switzerland had the required criteria (a temperature of 200°C at about 5 km depth and an existing large heat distribution system) for the development of Deep Heat Mining (DHM) to proceed. The project began in 1996 and progressed through the stages of site selection and preparation. During 2003-2006 drilling of the first well took place (reservoir definition) followed by the drilling of the 2nd and 3rd wells for production tests. Further testing will take place during 2007-2008, during which time the pilot plant will be designed. It is intended that the plant will be built and for operations to begin in the period 2009-2010. DHM research has also been conducted in the Geneva canton and a site selected for further studies.
There remains substantial room for growth in Switzerland's geothermal sector. The annual growth-rate for heat pumps is estimated at 15% and the Government is actively supporting research and development into geothermal energy.