| Abstract |
Exploration for geothermal resources began in Romania in the early 1960’s, arising from a hydrocarbon research program, which, as an unexpected benefit, also identified some promising geothermal areas. Within these areas, over 250 wells, drilled to depths between 800 and 3,500 m, showed the presence of low enthalpy geothermal resources. Completion and experimental exploitation of over 100 wells during the past 25 years has enabled evaluation of the exploitable heat available from these geothermal resources. Proven geothermal reserves in Romania are currently about 200,000 TJ for 20 years. The main Romanian geothermal resources are found in porous and permeable sandstones and siltstones (for example, in the Western Plain and the Olt Valley), or in fractured carbonate formations (Oradea, Bors, North Bucharest). The total capacity of the existing wells is about 480 MWt (for a reference temperature of 25°C). Of this total, only about 180 MWt are currently used, from about 80 wells (of which 35 wells are used only for balneology and bathing) that are producing hot water in the temperature range of 40115°C. For 2009, the annual energy utilisation from these wells was about 1,235 TJ, with an average capacity factor of about 0.22. More than 80% of the wells are artesian producers, 18 wells require anti-scaling chemical treatment, and 6 are used for reinjection. The main direct uses of the geothermal energy are: space and district heating; bathing; greenhouse heating; industrial process heat; fish farming and animal husbandry. During 2005-2009, 7 geothermal wells have been drilled in Romania with National financing. Some of these wells, drilled to depths ranging from 1,500 m to 3,000 m, have been successful, 3 of them producing geothermal water with about 70°C wellhead temperature, and one of them, near Oradea, about 1,700 m deep, with a wellhead temperature of about 90°C and an artesian flow rate of about 10 l/s right after completion, without acidizing. |