GeologicalSurvey of Slovenia

Characteristics of geothermal

potential, current utilization and its

future (challenges) in Slovenia

Andrej Lapanje, Nina Rman, Dušan Rajver

RENEXPO, BudapestRENEXPO, Budapest, , 6 May 6 May 20201111

GEOTHERMAL SYSTEMS IN SLOVENIA

GEOTHERMAL ENERGY POTENTIAL IN SLOVENIA

GEOTHERMAL ENERGY USE IN SLOVENIA

GEOTHERMAL ENERGY USE IN THE NE SLOVENIA

PRESENT AND FUTURE OF GEOTHERMAL UTILIZATION IN SLOVENIA

LECTURE CONTENT

Existence is dependant on geology, while their utilization on economic conditions

Potential for geothermal heat pumps utilization is not estimated in a wider scale but utilization is applied

In Slovenia mostly low-temperature aquifers in warm spring, sedimentary basin and basement of sedimentary basin systems exists

Middle and high-temperature aquifers in sedimentary basins and the basement are only presumed to exist

GEOTHERMAL SYSTEMS IN SLOVENIA

GEOTHERMAL SYSTEMS IN SLOVENIA

Various systems → different water properties → different use and problems

SURFACE HEAT-FLOW DENSITY (mW/m2)

Thinner solid crust in the NE Slovenia – higher than normal heat flow (>65 mW/m2)

EXPECTED TEMPERATURE AT 1 KM DEPTH

EXPECTED TEMPERATURE AT 3 KM DEPTH

Indications on possible high temperature reservoirs in NE Slovenia → yet to be proven

Geothermal energy – POTENTIAL FOR ELECTRICITY

Geothermal energy – POTENTIAL FOR ELECTRICITY

Potential high temperature reservoirs:- aquifer depth, thickness and boundaries- water yield, wellhead and reservoir pressure and temperature - water chemistry- produced energy- reinjection

Mg-6- temperature 202°C at 3739 m- no hydraulic tests were performed

Possible deeper drilling in existent boreholes for evaluation of the geothermal potential

Nearest demonstration geothermal electricity plants: Altheim (1 MWe), Bad Blumau (0.2 MWe)

Direct use

Thermal water is in usage at 30 locations Capacity: 66.8 MWt (in 2010) Energy: 774.6 TJ (in 2010)

> 4400 geothermal heat pumps (GHP)- open groundwater system (W)- closed system (H and V)- groundwater temperature 4-20°C

Capacity: 49.9 MWt (May 2010) Energy: 244 TJ (May 2010)

Total capacity in Slovenia (June 2010): 117 MWt Total energy use in Slovenia (June 2010): 1019 TJ

GEOTHERMAL UTILIZATION IN SLOVENIA

LOCATIONS AND TYPES OF DIRECT USE IN SLOVENIA

Lendava – De-icingDobrovnik – Orchids greenhouse

Murska Sobota – District heating

Moravske Toplice – Health resourt

Benedikt – Space heating

Pirniče - Meditation

EXAMPLES OF DIRECT USE IN SLOVENIA

SHARE (%) OF GTE CAPACITY IN SLOVENIA BY FIELD (June 2010)

GTE DIRECT USE INSTALLED CAPACITY (June 2010)

GTE DIRECT USE ANNUAL ENERGY USE (June 2010)

GEOTHERMAL ENERGY USE IN NE SLOVENIA

IDENTIFIED UTILIZATION PROBLEMS IN NE SLOVENIA

Degassing of methane, CO2, H2S Scaling High organic matter content Changes in chemical composition Water-level and yields decrease, interference Sand-clogging Pump cavitation

IDENTIFIED UTILIZATION PROBLEMS IN NE SLOVENIA

PROJECT ADDRESSING THE GEOTHERMAL IN NE SLOVENIA

Conceptual models:• Geological

• Hydrogeochemical• Geothermal

•Hydrogeological

http://www.t-jam.eu

PROJECT ADDRESSING THE GEOTHERMAL IN NE SLOVENIA

http://www.t-jam.euhttp://akvamarin.geo-zs.si/t-jam_boreholes/

PROJECT ADDRESSING THE GEOTHERMAL IN NE SLOVENIA

http://transenergy-eu.geologie.ac.at/ http://akvamarin.geo-zs.si/users/

Geothermal energy utilization rises, especially GHP

Strong interest in geothermal energy in the NE Slovenia Thermal water production rises with no reinjection applied Cascade use, operational and waste water monitoring are

mostly poorly applied Utilization problems are becoming more evident

Geothermal electricity is questionable in Slovenia Investors wanted for inactive wells exploitation (Janežovci,

Mislinjska Dobrava, Turnišče, Dobrovnik, Izola…) Investors wanted for drilling new wells (Goriška Brda,

Zasavje, Besnica, Petišovci…)

No national evidence on installed GHP No national monitoring system for deep geothermal

systems Only rare concessions granted, no control or deadlines

PRESENT AND FUTURE OF GEOTHERMAL IN SLOVENIA

Geologists & Drillers :

- current exploitation:- designing unified operational and national monitoring for sustainable production of thermal water

- dealing with aquifer changes: pressure drops, temperature and chemistry changes, interference, aquifer response to reinjection

- developing, modeling and testing doublet systems: reinjection into sand and loose sandstone reservoirs

- new research:- developing new low and high temperature geothermal sites

- exploring indicated potential high temperature deep geothermal aquifers

- exploring EGS potential in Slovenia

- identifying potential areas for GHP’s installation, elaborating expert basis, and estimating influence of its increasing installation on hydrogeological conditions in shallow aquifers

Future challenges

Future challenges

Users & Investors:- applying technological optimization at operating geothermal sites: higher efficiency of heat extraction, cascade use, prevention of scaling and degassing

- installing hybrid systems and cogeneration

- installing GHP’s in larger infrastructure objects according to European Energy Performance of Buildings Directive (EPBD)

- implementing operational monitoring on active wells

- developing new geothermal sites

Authorities:- enhancing national-wide geothermal and structural research by national and regional plans (financing & conducting research)

- enhancing GHP’s and other direct use geothermal installations by subsidies and expert support

- regulating new installations of water-water GHP’s

- issuing research and water permits and control their implementation

- designing, maintaining and interpreting national monitoring

- interpreting and controlling operational monitoring

AFP-1/95 photo: Geoprojekt

THANK YOU!