1. Geothermal energy – a clean and sustainable energy resource GEOTHERMIE.CH Schweizerische Vereinigung für Geothermie SVG Société Suisse pour la Géothermie SSG Swiss Geothermal Society SGS Dr. Roland Wyss, general manager

2. November 21, 2006 Content > Who we are > Development of use in Switzerland > Geothermal energy: basic principles > Utilisation possibilities  Borehole heat exchangers  Groundwater heat use  Geostructures  Deep aquifers  Water from tunnels  Enhanced geothermal system (EGS) > Planning > Advantages and disadvantages

3. November 21, 2006 Umbrella organisation GEOTHERMIE.CH > Support the use of geothermal energy  Education and advanced training  Information of public and specialists  Support the realisation of new developments  Networking: politicians, administration, industry, research, consulting, user  Links to other networks (e.g. renewable energy)  Links to geothermal organisations abroad > Sponsorship: Swiss Geothermal Society (SGS) (since more than 15 years) > Commissioned by: Swiss Federal Office of Energy

4. November 21, 2006 Umbrella organisation

5. November 21, 2006 Content > Who we are > Development of use in Switzerland > Geothermal energy: basic principles > Utilisation possibilities  Borehole heat exchangers  Groundwater heat use  Geostructures  Deep aquifers  Water from tunnels  Enhanced geothermal system (EGS) > Planning > Advantages and disadvantages

6. November 21, 2006 Geothermal energy

7. November 21, 2006 Development of the use of geothermal energy I > ~ 35’000Borehole heat exchangers > ~ 3’700groundwater heat use > 2005:750 km drilled for borehole heat exchangers Stand ca. 1998: Drilled boreholes for heat exchangers

8. November 21, 2006 Development of the use of geothermal energy II > Produced heat energy since 1990 [GWh] Author: Geowatt AG

9. November 21, 2006 Development of the use of geothermal energy III > e.g. 2003: produced heat energy 1110 GWh Source: Geowatt AG Deep borehole heat exchanger 0.1% Geostructures 1.2% others 2.5% Groundwater 9.9% Borehole heat exchanger 56.0% Deep aquifers 3.4% 28.2% Tunnel water 1.2% 622 GWh 37 GWh 313 GWh 110 GWh 14 GWh 1 GWh 13 GWh Spa

10. November 21, 2006 Content > Who we are > Development of use in Switzerland > Geothermal energy: basic principles > Utilisation possibilities  Borehole heat exchangers  Groundwater heat use  Geostructures  Deep aquifers  Water from tunnels  Enhanced geothermal system (EGS) > Planning > Advantages and disadvantages

11. November 21, 2006 Geothermal energy: from where it comes from > Geothermal energy = heat, stored within the earth. > Origin: mainly natural decay of radioactive elements. > 99% of the earth is hotter than 1000 °C. Only 0.1% is cooler than 100°C. > Average heat flow: 60 mW m -2. > Geothermal heat flow through earth surface: 40 × 10 12 W = 40’000’000 MW = 40’000 GW = 40 TW ( 1 nuclear power plant: 1000 MWe)

12. November 21, 2006 Temperature distribution in the earth > temperature distribution from surface to core > Seasonal temperature distribution near the earth surface

13. November 21, 2006 Content > Who we are > Development of use in Switzerland > Geothermal energy: basic principles > Utilisation possibilities  Borehole heat exchangers  Groundwater heat use  Geostructures  Deep aquifers  Water from tunnels  Enhanced geothermal system (EGS) > Planning > Advantages and disadvantages

14. November 21, 2006 Overview utilisation possibilities > Categories according to:  Depth  Temperature  Heat source  Type of development  Utilisation technique not presented in this scheme: horizontal pipe heat collectors, geothermal baskets, geostructures Author: CREGE, Neuchâtel

15. November 21, 2006 Borehole heat exchangers I > Drilling depth from 50 to 400 m > Useable temperature up to 20 °C > Closed cycle with heat carrier fluid (water-glykol) > Until now 35’000 installations > about 750 km boreholes in 2005 > Restrictions in groundwater Quelle: CREGE, Neuchâtel

16. November 21, 2006 Borehole heat exchangers II > Fluid cycle:  Example: Grundag Duplex ® material: polyethylene > Heat pump:

17. November 21, 2006 Fields of borehole heat exchangers > For heating in lager buildings > Ideal for cooling Quelle: P. Berchtold

18. November 21, 2006 Fields of borehole heat exchangers, examples I > Mediaswiss, Teufen (AR):  Heating and cooling with 15 borehole heat exchangers, depth 137 m each > Salzmann Medico, St. Gallen:  Heating with 17 borehole heat exchanger, depth 280 m each

19. November 21, 2006 Fields of borehole heat exchangers, examples II > Dolder Grand Hotel, Zürich :  1 GWh for heating und 1 GWh for cooling  70 borehole heat exchangers, 152 m each (> 10‘000 m)

20. November 21, 2006 Risks requires a good technical planning and monitoring > Artesian groundwater > Water bearing, loose formations > Subsidence due to structure fail > Drilling problems > Gas seeps Quelle: Beat Keller

21. Jona: November 24, 2004

22. November 21, 2006 Groundwater heat use > Well depth: 5 to 20+m > Usable temperatures: ca. 10 – 12 °C > Water as heat carrier > High efficiency > ca. 3’700 existing installations > Restrictions and Risks:  Permit  Well yield  Recharge Source: Eberhard + Partner AG, Aarau

23. November 21, 2006 Geostructures > Use of geothermal energy from foundation of a building > Cooling possible > Technical guide by SIA (D 0190) > Examples:  Zurich Airport, Dock Midfield Source: CREGE, Neuchâtel Source: E. de Lainsecq Quelle: D. Pahud

24. November 21, 2006 Geothermal baskets > Near surface use of geothermal energy > Applicable for small buildings (where borehole heat exchanger are not possible; efficiency and costs about the same) Quelle: Handbuch Erdwärmekörbe, BfE, 2005

25. November 21, 2006 Horizontal pipe heat collector Source: Clauser

26. November 21, 2006 Deep aquifers, geothermal springs I > Borehole depth: between 500 and 2000 m. > Usable temperatures: ca. 60 – 80 °C  direct heat use possible > Heating of larger buildings possible > Oldest form of utilisation of geothermal energy: Spa Yverdon-les-bains, Foto: F.-D. Vuataz Direct heat use in 2000 worldwide about 17‘200 MWth (F.-D. Vuataz)

27. November 21, 2006 Deep aquifers, geothermal springs II > Scheme of the doublet system and the heat distribution network in Riehen (BS) Quelle: Vuataz 2003 > Location, depth of deep geothermal wells in Switzerland (1987–1998, Source: SFOE)

28. November 21, 2006 Deep aquifers, geothermal springs II Source: Vuataz 2003 > Location and depth of deep geothermal wells in Switzerland (1987–1998) (Source: SFOE)

29. November 21, 2006 Use of tunnel water

30. November 21, 2006 Use of tunnel water: examples 5400 l/min, 16 °C, 960 kW Heating of 177 appartments Furka base tunnel (VS) Ricken tunnel (SG) 690 l/min, 12 °C, 156 kW Heating of a school building, incl. gym hall and assembly hall Base tunnels in the alps: very good potential (projects in planning

31. November 21, 2006 High enthalpy geothermal energy – electricity production Total power production worldwide: 8 GW

32. November 21, 2006 High enthalpy geothermal energy – electricity production Scheme: Enhanced Geothermal System (EGS) > Drilling depth: 4 – 6 km > Temperatures: 200°C > Examples:  Lardarello (Italy): since 1827; first geothermal electricity production worldwide  Soultz-sous-Forêts (France): European EGS-project planned: Electricity: 20'000 MWh Heat: 100'000 MWh per year  Basel: Realisation: 2006 – 2009 planned: 6 MW electricity (10‘000 HH) 17 MW heat (2‘700).

33. November 21, 2006 Content > Who we are > Development of use in Switzerland > Geothermal energy: basic principles > Utilisation possibilities  Borehole heat exchangers  Groundwater heat use  Geostructures  Deep aquifers  Water from tunnels  Enhanced geothermal system (EGS) > Planning > Advantages and disadvantages

34. November 21, 2006 Planning > Example: Zürich > Example: St. Gallen > Different regulations in cantons > Permit given by each canton > Data often available on www

35. November 21, 2006 Instruments > Regional information centres > Local consulting companies (geologist) > Specialised planning engineer > Local administration > Regulations by SIA (in preparation) > New guide by Federal Office for the Environment FOEN (in preparation) > Quality control (heat pumps, drilling companies) > WWW

36. November 21, 2006 Content > Who we are > Development of use in Switzerland > Geothermal energy: basic principles > Utilisation possibilities  Borehole heat exchangers  Groundwater heat use  Geostructures  Deep aquifers  Water from tunnels  Enhanced geothermal system (EGS) > Planning > Advantages and disadvantages

37. November 21, 2006 Comparison of common heating systems > Environmental issues > Economics for heating and production of war water in a modern, isolated house (one family) Source: WWF, 2006: «Klimaschutz spart Geld beim Wohnen»

38. November 21, 2006 Advantages and disadvantages of geothermal energy Advantages > Local resource, short transport distance > Clean, CO 2 neutral > Always available > Renewable > No storage capacity needed > Everywhere applicable > Heat: reality proofed > Small required space Disadvantages > High investment costs (drilling) > Deeper underground: exploration risks (not temperature but water cycle) > Electricity power production: little experience