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Data on thermal water sources with outflow temperature of 30 °C and above were analyzed from the N-ern parts of Bosnia and Herzegovina, Serbia and Croatia, S-ern parts of Hungary, W-ern parts of Romania, and NE-ern parts of Slovenia, altogether from an area of 99,347 km2. The overview identified 771 geothermal sources; only 7 were thermal springs. The average well depth is about 1.2 km. About 13% of wells are younger than 10 years, additional 17% below 30 years; while 26% are older than 50 years. Average thermal water outflow temperature is 54 °C being the highest, 170 °C, in Croatia. Most thermal water is produced from basin fill sediments—Lower and Upper Pannonian (Mio-Pliocene) loose sandstones which are tapped by 86% of wells. The rest appertains to basement rocks—fissured, fractured and karstified Paleozoic, Mesozoic and Middle Miocene metamorphic, carbonate and siliciclastic rocks. In total, 72% sources hold water rights, 6% mining rights, 2% geothermal rights and 1% has no rights. The permits allow much higher water abstraction as currently listed. Usage for bathing and balneology encompasses 24% of all active sources (155), some of these also with heating (23). 104 objects (16%) are used for heating, also district heating (13) and individual space heating (3). An additional 10% (70) are used in agriculture, mainly greenhouse heating. There are 41 reinjection wells (5%). It is primarily in Hungary that drinking water (17%), industrial usage (5%) and monitoring wells (2%) are also common. [ABSTRACT FROM AUTHOR]

The main objective of ThermoMap project was to develop a methodology for estimating the thermal conductivity and heat capacity in the first 10 m of the ground, in order to identify areas favourable for installation of ground heat source pumps. Based on best available data regarding climate, soil type, soil texture, geology and water table depth, maps of the thermal parameters were computed in test areas from partner countries. Three depth layers were investigated: 0-3, 3-6 and 6-10 m, each one characteristic for different types of ground source heat pumps. In order to check the computed values, samples were collected in test areas and measured in the laboratory. This paper presents the results of the validation performed for Constanta county test area (Romania). Samples of soil and Quaternary formations collected in the Danube terraces and the Black Sea high shores were analyzed in the laboratory for determining the bulk density, soil texture, thermal conductivity and heat capacity. The measurements were performed on samples simulating the three possible system conditions: unsaturated (arid or humid) and saturated conditions. The values determined by laboratory measurements were interpolated in order to obtain the appropriate thermal conductivity values for the defined bulk density values used by ThermoMap for each depth layer. The comparison between ThermoMap computed data and the laboratory measurements of thermal conductivity showed that out of three samples, at least two are within the specified error range of ±25 %. The best fit occurs for layer 3-6 m, whose assigned density is closer to the mean of measured bulk density values. [ABSTRACT FROM AUTHOR]