Final Program EXPRES 2012 - Conferences

Present and Future of Geothermal Energyin Heat Supply in HungaryGyné, Halász Mrs.Institute of Environmental SystemsFaculty of Mechanical EngineeringSzent István University, Gödöllő, Hungaryhalaszne@yahoo.comAbstract—The paper focuses on advantages of heatutilization of thermal water with or without exploitationcontra regular gas boiler supplied heating systems.I. INTRODUCTIONToday the most important issue of energy supply is thatthe fossil primer energy source of the Earth is limited.Substitution of it is indispensable because environmentalpressures require reduction of CO 2 emission. Towardsnext generations one of the main aims of the researches isto create energy systems that operate with less and lessprimer energy source thus insure the sustainabledevelopment and meet the environmental protectioncriteria.The geothermal energy orientated internationalprofessional literature claims geothermal heat as the mostpure energy source.Hungary’s geothermal production goes back almost acentury, and has won a prestige in the World’s geothermalenergy sector. It is well known that Hungary’s geothermalpotential is among the world’s best territories (notcounting the active volcanic areas). Heat flow density ishigh and can reach up to 100 mW/m 2 value and thegeothermal gradient maximum values are close to 60°C/km 2 , but there are no large enthalpy geothermal fieldsin Hungary [2]. Because of the increased need towardsenvironmental friendly technology, a significant increaseof national geothermal heat production is expected in themedium and long term.II. GEOTHERMAL PERSPECTIVE OF HUNGARY UNTIL2020Hungary’s primer energy consumption in 2010according to statistic data by Hungarian Energy Officewas 1086.7 PJ. Close to 58 % of the primer energy wasimported. 74.7 % of the consumed primer energy wasfossil fuel, 7.6 % (82.1 PJ) was renewable energy and 17.8% was primer electric power. 64.3 % (698.7 PJ) of theprimer energy has reached the end-user. The main endusersare households with 22.1 % (240.6 PJ). 6.3 % (49.1PJ) of the gross final energy consumption were renewablesources, of which nearly 9 % is geothermal energy.The most important document that determines thefuture of the geothermal energy is Hungarian NationalRenewable Energy Action Plan (hereinafter referred as to:NREAP) [6]. NREAP’s indicators help us to conclude thedevelopment of the coming years. NREAP determinesfour times increase regarding the thermal water based heatsupply. Table I. shows the growth of the main segments.The plans are ambitious, but they are in accordancewith the technology possibilities of Hungary’s geothermalpotential and correspond to the major Europeandevelopment appropriations [5].TABLE I.PLANNED GROWTH OF THREE MAIN SEGMENTS OF GEOTHERMAL HEATPRODUCTION [6]Heat pumps,Supplied heat/yearWithin heatpumps:Ground sourceheat pumps,Supplied heat/yearThermal waterbased direct heatsupplySupplied heat/yearGeothermal basedelectric powerproduction,PowerGeothermal basedelectric powerproduction,Energy/year2010 2020 Growth(2020/2010)0.250 PJ 5.99 PJ 5.740 PJ 23.960.208 PJ 4.48 PJ 4.272 PJ 21.544.23 PJ 16.43 PJ 12.2 PJ 3.880 MW 57 MW 57 MW -0 GWh410GWh410GWhDue to the development of the renewable energyindustry, NREAP appropriates 70–80 thousand permanentwork places in this sector in 2020. If this occurs, then itsignificantly helps to decrease the negative effects of theeconomic crisis.III. ENERGY AND EXERGY ANALYSIS OF SYSTEMSSUPPLIED WITH DIFFERENT HEAT PRODUCERSEnergy and thermodynamic analysis of heat supplysystems supplied with different heat producers (electricpower energy, regular and condensation gas boilers,electric power operated heat pumps and thermal water)proved that the heat utilization of thermal water (forheating, cooling with heat, and domestic hot waterproduction) is the most favorable technical solutionregarding energy and exergy efficiency. This has a simpleexplanation: fossil fuel used for space heating anddomestic hot water production as low exergy functions is-59