21. Hydrogeothermal Potential of the Belgrade City Area, the Capital of Serbia First Assessment

The first assessment of hydrogeothermal potential of the Belgrade city area was carried out up to the depth of 300 m. The criterion for defining the in-depth cut of the research was based on financial viability of resource exploitation, and it is related to the method of drilling exploitation boreholes. The temperatures of the groundwater resources up to 300 m deep, range from 12 to 25 °C, so their use for the sake of the building air-conditioning is determined by the application of heat pumps. According to the assessed quantities of hydrogeothermal resources (kg/s), the temperature difference which can be achieved on the temperature exchanger (°C) and, finally, the specific heat capacity of the water (KJ/kg/°C), the total hydrogeothermal potential of the Belgrade city area is approximately 1200 MW. Half of the total heating requirements of the urban residential and business funds in the Belgrade city area is met with the district heating system, and the other half is met with the electric energy, up to 20 %; gas, 20 %; and hard mineral fossil fuels (coal, wood), 10 %. The total installed capacity of the heating plants is about 2500 MW, and it can be concluded that hydrogeothermal resources could meet about 50 % of the city’s heating needs. According to the above-mentioned data, hydrogeothermal resources are a strategically significant resource for the further development of the Belgrade city area.