Geothermal district heating – Case study of Szeged, Hungary
János Szanyi, Máté Osvald, Balázs Kóbor, Tamás Medgyes, Tivadar M. Tóth
University of Szeged, Hungary * [email protected]
EuroWorkshop: Geothermal – The Energy of the Future 18 – 19 May 2017, Fira, Santorini, Greece 1
EuroWorkshop: Geothermal – The Energy of the Future January 24-25 2017, Budapest, Hungary Geothermal thematic map of Europe and Hungary
(based on Sanner, B., 2008)
(Dövényi, P., Horváth, F., 1988)
Szeged
2 Geological background
Due to plate tectonic events a quick subsidence of the surface occurred that made the Pannonian deep sea.
Szeged In the place of the former sea a huge sedimentary basin remained with sedimentary 1000 Duna Tisza 0 Q sequences up to -1000
P a 2 -2000 6-7,000 m thickness.
-3000 P a 1
-4000
-5000 Pre-P a -6000
-7000
-8000
3 Thickness of the Upper pannonian sequence
4 Hydrodinamical background
Tóth-Almási, 2001 Locations of thermal wells
Wells in sandstone Wells in carbonate
6 CH-fields surroundings of Szeged
Oil fields CH-wells surroundings of Szeged The pressure drop in the aquifer
Pressure (MPa)
) (m) a.s.l level
(m Water Depth
Q (l/min)
9 The geothermal project of the University of Szeged
10 Geothermal cascade system in downtown
Investment: 6.6 million € Yearly profit: 0.45 million € Geothermal cascade system in Új-Szeged
Investment: 4.2 million € Yearly profit: 0.37 million € University of Szeged – Green University
In December 2014 Szeged secured a place among the 10 best European university towns on the Condé Nast Traveler website. The renowned travel magazine mentions Szeged as being the 8th best university town in Europe and the. University of Szeged as the most prestigious university of Hungary.
The greenest Hungarian university is still the university of Szeged and at the same time it even improved its „green position”: out of 360 applicants it reached 19th place on the newest world ranking list of 2014. In the European green top list the universitas on the bank of river Tisza gained 11th place. Main parameters of last projects
Mórahalom Szeged University Csongrád Makó Produced geothermal energy (GJ/y) 18 000 86 000 55 931 67 000 Natural gas reduc on (m3/y) 482 000 2 900 000 920 000 2 192 000 CO2 reduc on (t/y) 1 400 5 900 1 663 3 847 Spending on investment (€) 1 753 000 10 800 000 1 384 000 3 162 000 Investment/produced energy (€/GJ) 97.4 125.6 24.8 47.2 Maintenance cost (€/y) 138 300 473 000 187 000 172 000 Pay-back (y) 10.5 13.5 5.7 8.1
14 Heating circuits of the district heating in Szeged
15 Parameters of the planned geothermal circuit
Construction of the 3.5 MWth project • 1 production well (1995 m) • 2 injection wells (1350 m; 1750 m) • pipe line ~ 3300 m • 25 new heating centres • Online PLC control system
The heat is utilised through a main titanium heat exchanger. The primary circuit fluid is 90°C in temperature and has a flow rate of 70 m3/h and the secondary circuit fluid has an 88/50°C heat step.
• HC-I (Odessza heat circuit 1) : 4950 kW + 250 kW domestic hot water • HC-II (Odessza heat circuit 2): 4480 kW + 250 kW domestic hot water
The hydraulic effect of the new wells Natural gas and thermal energy use
There are 12 main consumer blocks within these 2 circuits. If the ambient temperature is warmer than +2°C, which is approximately 80% of the total heating days, the need of 9 consumer blocks is fully satisfied by geothermal energy from the 2 heating circuits. All of the heat demand can be fully covered by geothermal energy if the ambient temperature is warmer than +7°C. By design, 70% of total heat demand will be satisfied by geothermal in an average winter
Natural gas use Geothermal Natural gas saving U lised geothermal (GJ) ra o (%) (GJ) energy (GJ) HC-I 37,629 97.4 36,651 32,986
HC-II 44,348 47.2 20,932 18,839
Total 81,977 70.2 57,583 51,825 Outcomes of the project
Environmental impact: • Produced geothermal energy: 51 825 GJ/y • Natural gas reduction: 1 700 000 m3/y
• CO2 reduction: 2 957 t/y
• NOx reduction: 2 992 kg/y
• SO2 reduction: 343 kg/y The greenhouse gas emission reduction prognosis:
90,000 t CO2 equivalent for 30 years’ lifetime
Economic impact: • Spending on investment: 4 200 000 € • Investment/produced energy: 1 200 €/kW
• Specific investment of CO2 reduction: 1 400 €/t • Maintenance cost: 250 000 €/y Optimal use of thermal water
20 Conclusions
− 70% decrease in natural gas consumption at the connected buildings − Running costs 70% less than gas systems
Most important criteria of economical Geothermal project
• Good geothermal conditions (heat and aquifer) • Appropriate heat market – sortable into cascade system (Existing district heating systems can expand further and new users can be implemented) • Predictable economical climate • Stable legislation • Money, Money, Money Thank you for your attention!
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