1. Energy from the deep subsurface, potentials of geothermal for a sustainable supply of increasing energy demands Annamária Nádor Geological and Geophysical Institute of Hungary 3rd European Energy Conference, October 27-30, 2013, Budapest

2. Current energy consumption is unsustainable - actions are urgently needed!  growing energy demand  restricted and uneven distribution of fossil fuels → supply security  climate change debate: enhanced use of fossil fuels → increased atmospheric CO 2 concentration → global warming, extreme events increase of renewables in the energy mix: integrated economic development innovative and competitive technologies structural changes in the industry and agriculture new working places decentralized → rural development Kyoto Protocol 20/20/20 by 2020 COM(2006)848  cut energy consumption (fossil fuels) and CO 2 emisssions  increase energy efficiency  increase renewable energy sources (RES)

3. National characters  Import dependency: ~ 83% of hydrocarbons  Security supply, focus on own resources Main aim: ensure the longterm sustainability, security, and economic competitiveness of energy supply in Hungary Increasing the share of renewables New Energy Strategy of Hungary 2011-2030 Russian import 20 billion m 3/ y European market 4,5 billion m 3 /y Total consumption: 12 billion m 3 /y Own production: 1,8-2,0 billion m 3 /y 4,1 bn m 3 /yr 4,5 bn m 3 /yr 6,5 bn m 3 /yr RES Directive (2009/28/EC): 13% RES for Hungary Hungary: not an obligation but a POSSIBILITY for economic growth: 14,65% RES by 2020 (120,57 PJ)

4. 2010 2020 Distribution of RES in the Electricity and Heating-Cooling sectors Contribution of geothermal energy 2010 9% of total RES 2020 17% of total RES Direct heat (PJ)4,2314,95 Electricity production (MW) 057

5. Geothermal energy: definition and basic concepts Geothermal energy is energy stored in the form of heat below the surface of the solid earth (shallow – stored solar and deep) Origin of heat: decay of radioactive isotopes: U 238, U 235, Th 232, K 40 4300°C 3700°C 1000°C Total volume of the Earth Heat flow Crust (rich in radioactive isotopes) 2%8 x 10 12 W mantle82%32.3 x 10 12 W Core (no radioactive isotopes) 16%1.7 x 10 12 W Heat content of the Earth: 12,6∙10 24 MJ Takes over 10 9 years to exhaust via global terrestrial heat flow

7. high enthalpy (el. power) high temp. basins (el. power, district heating) medium temp. basins (district heating) everywhere shallow geothermal Main geothermal provinces of Europe EGEC

8. heating → thermal expansion of stored groundwater → lower density, rise and replaced by colder meteoric water of high density coming from the margins of the system artificially enlarged fractures as „heat exchangers” in deep lying hot rock bodies Hydrogeothermal (convectional) systems Enhanced Geothermal Systems

9. Lindal diagram Cascade utilization of geothermal energy >150°C: high enthalpy - electricity generation < 150°C: low-medium enthalpy - heating- cooling + many others

10. Thermal bath of Caracalla, Thermae Antoninianae 1904: the world’s first geothermal power station with a 10kW generator at the Larderello dry steam field, Italy, Tuscany

11. Geothermal potential of Hungary Favorable conditions due to Miocene basin formation (10-12 My ago) Average terrestrial heat-flow: 100 mW/m 2 Geothermal gradient: 45 °C/km Thickness of the lithosphere

12. Subsurface temperature distributions (°C) -1500 m -2500 m Zilahi Sebess et al. 2012

13. 1 Pannonian basin - hot sedimentary aquifer (convectional flow system): utilization of geothermal energy ≈ thermal groundwater / fluid abstraction Main geothermal reservoirs Paleo-Mesozoic fractured, karstified basement rocks Mio-Pliocene porous basin fill: multi-layered sandstones, shales depth (top)>2-3000 m600-1500 m temperature>100-150 °C50-100 °C prospectpower, CHPdirect heat, balneology  high heat flux  thermal „insolation” of basin fill sediments  regional groundwater flows driven by hydraulic potential between recharge and discharge areas

14. Current utilization schemes in Hungary Nádor et al.2013 595 thermal wells (outflow T > 30 °C) Annual production: 68,44 million m 3 (2011)

15. Current utilization schemes Nádor et al.2013

17. Renewability vs. sustainability Renewability – attribute of the energy source The energy extracted from a renewable energy source is always replaced in a natural way by an additional amount of energy and the replacement takes place on a similar time scale as that of the extraction” (Axelsson et al., 2001) Geothermal energy: replacement of heat and fluid Sustainability – how we use it? „... for each geothermal system and for each mode of production there is a certain level of maximum energy production, below which it will be possible to maintain a constant energy production for a very long time (100 - 300 years)” (Axelsson et al., 2004)

18. Balanced heat-fluid production High production rates exceeding long-term rate of recharge can lead to depletion of the reservoir, which can be avoided by reinjection of used fluids. Balanced fluid/heat production (not producing more than the natural recharge re-supplies) is fully sustainable. These rates are limited and often not economical for use

19. Hydrogeological models: different scanarios only SK csak SK only HU SK, HU, SLO present SK, HU, SLO 5X TRANSENERGY project: transboundary hydrogeothermal systems Tóth, 2012

20. Hydraulic heads field in Upper Pannonian geothermal aquifer, pumpig wells scenario Hydraulic heads field in Upper Pannonian geothermal aquifer, doublets scenario TRANSENERGY project, Danube basin pilot area (SK-HU) Svasta, 2013

21. Concluding remarks  Geothermal energy is an important RES and has huge potentials for growth  Geothermal energy is renewable on time-scales of technological /societal systems, though it is an exhaustible energy source  Production should be limited to sustainable levels which secures the longevity of the resource (not exceeding natural re-charge and/or re-injection)  Due to the favorable geological setting, the geothermal potential of Hungary is very good  In the current utilization balneology is overwhlemming, direct use in agriculture is significant, but much beyond the potentials in district heating  Ambitious NREAP numbers forecast a 3,5 times growth in direct heat and establishment of power production by 2020

22. Responsible for the RDI in Hungary (establishing the national RDI strategies and policies, their implementation and monitoring. Supports the uptake of local innovations in the Hungarian and international the market. Promote and help the foreign investments in innovation area. Coordinates and is responsible for the international and bilateral cooperations in the area of technology and science. Incubation of the young innovative enterprises and RDI activities of the SME-s. National Innovation Office

23. Thank you for your attention! nador.annamaria@mfgi.hu tel: +36-30-924-6823