| Abstract |
The heating and cooling sector plays an important role with respect to our primary energy demand. As in the EU and allover the world heat and cold accounts for about 50% of the final energy consumption. The potential of geothermal energy for this sector and not just for electricity supply is vast: The RHC (Renewable heating and cooling panel – European Technology Platform) estimates in 2020 over 25% of heat consumed in the EU could be generated with renewable energy and by 2030 RHC technologies could supply over the half of the heat used in EU-Europe. Besides geothermal energy the use of biomass and solar power are the basis of RHC. The reason for the optimistic look into a renewable future in Europe is the increasing use of highly effective district heating systems with geothermal energy as base load. Figure 1: Main European District Heating Sites (Ungemach, 2007) Current state In some countries of Europe district heating systems mostly using conventional fossil burning have operated for centuries. More and more the use of renewable energy like biomass, waste, or geothermal is becoming attractive. As the use of local heat is the fundamental idea behind modern district heating systems they become more and more relevant. Heat, cold and fuel sources that normally would be lost, remain in the local systems for both: the residential as well for the non-residential sector including industries. The use of geothermal district heating is already spread across Europe. Only 10 of 33 European states didn’t have geothermal district heating installed in 2012. A large number of geothermal district heating systems can be found in France (~42systems, 250MWth), Iceland (~32systems, 2,300MWth) and Germany (~23systems, 200MWth). Right now the installed geothermal capacity of whole Europe adds up to 4,900MWth. 1,700MWth of this capacity is in EU-member states. It is estimated that the number of geothermal district heating systems in Europe may increase. By 2015 four more states are expected to be equipped with these systems. Existing systems as in Germany, France and Hungary will increase. This projected development has the advantage, that geothermal district heating are efficient ways concerning costs, and that they are systems with the smallest emission of CO2. Furthermore geothermal energy is an inexhaustible heat source which has a high security of supply for it is not affected by outside temperature, season or time of day and can be installed in every European state. Germany Graph 1: Thermal capacity of geothermal plants in Germany; (Statistika, 2013) In many Bavarian city i.e. Ismaning holes are drilled to contribute to the heat supply via a district heating system (EneffWärme, 2012). In Germany more than 20 deep geothermal projects are operational, 20 are under construction and about 40 planned. All providing heat, six of them producing electricity as well. These figures show a strong and rising interest in GDH in Germany. The city of Munich with 2 million inhabitants wants to generate 100% of its heat demand on renewable energies mainly geothermal energy until 2040. Table 1: Development of Geothermal District Heating Systems For 2015 27 of the 33 European countries are expected to be equipped with geothermal district heating systems. In this interval of three years especially the number of systems in Germany and France are meant to increase. The Advantages of geothermal district heating systems compared to fossil fuel heating systems are as follows: - Geothermal energy is an inexhaustible heat source  renewable energy - Geothermal energy |