Geothermal Drilling for Space Heating in the Town of Szentlőrinc in SW Hungary

Abstract

The area in the vicinity of town Szentlőrinc, SW Hungary, was evaluated in respect to geothermal energy and the first drilling took place from April to September 2009. Extensive quantity of existing geosciences data is available for the area and has been used to site the first well for utilization of geothermal water for space heating in the vicinity of the town. The data that has proven to be of the most value is geological data from existing wells along with temperature measurements in these wells. Four seismic lines exist in the area gave valuable information on the geology and depth to the expected reservoir and locations of promising fault zones. To strengthen the interpretation of the geosciences data an AMT/MT and gravity survey was conducted in 2008 in an attempt to find zones with higher porosities and permeability. Based on thorough analysis of available data well site was chosen with the aim of penetrating major fault zones within the basement indicated by seismic data, where the AMT/MT and gravity results imply potential geothermal zone, and where wells indicated favorable temperature and reservoir rock type. Due to technical reasons the drilling took longer time than expected. The well was successfully finished giving 20 l/s in airlifting of over 80°C hot water with 5–10 l/s of artesian flow. The geothermal energy will be used in the local district heating system.