Andrej Lapanje and the TRANSENERGY team

1. Recommendations for sustainable management of transboundaryhydrogeothermal resources at cross-border pilot areas Bad Radkersburg-Hodoš Area (Slovenia-Austria-Hungary) Andrej Lapanje and the TRANSENERGY team Final Event of project TRANSENERGY – Transboundary geothermal energy resources of Slovenia, Austria, Hungary and Slovakia Vienna, 24. June 2013

2. Content • Aims of research • Overview of past knowledge and utilisation status • Pilot area conceptual models • Geothermal potential assessment • - natural state and different production scenarios - • Current vs. proposed management and utilisation • - recommendations on transboundary management -

3. Geographical overview Alltogether more than 110,000 inhabitants Main industry: - Agriculture - Machine industry - Tourism

4. Aims of Research Scope of investigation: Geothermal system in the Preneogene basement rocks within the Raba fault zone in the Radgona – Vas tectonic halftrench Scientific • What is the real extent of the Prenogene geothermal aquifer? • Does this aquifer have an active recharge and how are the recharge mechanisms working ? Where the recharge area is? Management • Do the already drilled boreholes in the Prenogene geothermal aquifer hydraulically interfere and to what extent? • What kind of measures is needed to reach sustainable utilisation? • How much energy (and mass) it is possible to extract in a sustainable way in future?

5. Structural overview

6. Previous status of knowledge • Singularprojects: • - oilandgas, • geothermal, • undergroundgasstorage Synthesis: NANUTIWA, 2005 TRANTHERMAL, 2008 Dilema (Suete, Common project proposal, 2011): Recharge from infiltration in Bakony Mts. Wide spreading percolation from overlaying sediments Potential mechanism of recharge (Domberger & Schreilechner 2007)

7. Oveview of utilisation A SLO No natural discharge features No observable changes in production and quality in Benedikt No reported changes in production and quality in Bad Radkersburg

8. Utilizationchallenges The water is technically hardtouse: • high scaling potential Current mitigation: • use of inhibitors • periodicalacid flushing Solution for future (BAT): • closed system with reinjection (geothermal doublet)

9. Geological setting • NW border of the Mura-Zala neogene sedimentary basin • fractured Mz carbonates and Pz metamorphic rocks - Raba fault zone • deepening towards NE to over 4000 m

10. Hydrogeological and geochemical setting • The chemical composition of thermal water in Bad Radkersburg and Benedikt is similar • Permeability is highly anisotropic, double porosity principle and depends on the structural position within the fault zone • The recharge from HU is unlikely as: • observed hydraulic heads in HU are lower than in Benedikt, Bad Radkersburg and Korovci • mineralisation of water in thermal karst (east of the pilot area) is very high in comparison to Benedikt - Bad Radkersburg area

11. Natural geothermal conditions • Temperature in the Preneogene basement rises towards NE • Convective flow cell in Benedikt with supposed base at about 2,000 m • Locally enhanced permeability of fissured rocks in the geothermal aquifer

12. Natural potential of the Preneogene aquifer

13. Methodology - Numericalmodelling • Coupledflow and heat transfer • FEFLOW code • Twodistinctivelithologies • The Raba fault zone

14. Geothermal potential due to differentproduction scenarios (reinjection or no reinjection) Production without reinjection: Hydraulic depression would reach Bad Radkersburg only if very high abstraction rates or preference flowpaths were present. Production with reinjection - geothermal doublet Korovci : Potential cool-down effects of the reinjected water front, i.e. thermal breakthroughis unlikely after 50 years in the pumping regime 20 l/s and thermal regime 80 °C / 35 °C.

15. Current management Bilaterally agreed monitoring program and passive monitoring for this aquifer not exist at present

16. ACTIONS! • JOINT MANAGEMENT • Monitoring • Reporting • Permitting / protecting • USE OF BEST AVAILABLE TECHNOLOGY • BENCHMARKING • FURTHER RESEARCH

17. Joint management . Aim of monitoring is to get a representative information about the used part of the deep groundwater aquifer (M. Samek) SI-AT ‘’Mura/Mur’’ commission opened the issueof transboundary aquifer →conclusions can be prepared Follow the best-practice example of the Upper Austrian – Bavarian »Malmkarst« reservoir

18. Mura/Murcommissionshould take theinitiative! Using results of pilot area research: The outcome of the modelingcan be used establishing the water protection area. The Bilateral database for information exchange about status and production data can be developed under patrimony of Bilateral Commission. The program of bilateral monitoring can be agreed between Slovenian –Austrian ‘’Mura/Mur commission’’ and users from both countries. Monitoring should rely on existing production boreholes, no passive monitoring is proposed.

19. Use of best available technology Anynewutilisationshouldconsidertheuseofdubletsthus: • preventingtechnicaldifficulties, • minimizeenvironmentalimpact, • minimizeimpact to theaquifer, • minimizethe interference amongusers. Allexistentusersshouldfollow theuseofdoublets.

20. Benchmarking

21. Further research Improvement of knowledge about geological model (collection of new data, geophysical measurement) Implemetation of geothermal doublet (technical aspects, influence to the coupled hydravlic-temperature field Investigation of the potential in NE part of the aquifer at the border region between Slovenia and Hungary for production of electricity by binary power plants (geophysics)

22. Co-workers on theBadRadkersburg – Hodoš pilot area GBA dr. Rudolf Berka Fatime Zekiri Magdalena Bottig mag. Gregor Goetzl GeoZS Tadej Fuks dr. Mitja Janža Dejan Šram Simon Mozetič mag. Dušan Rajver Mirka Trajanova Nina Rman mag. Joerg Prestor dr. Igor Rižnar dr. Bogomir Jelen Helena Rifelj mag. Andrej Lapanje MFGI György Tóth dr. Gyula Maros dr. Ágnes Rotár-Szalkai dr. Teodóra Szőcs Thank you for your attention!