Geothermal energy sources identification after joint interpretation of geo-data from the Baia Mare area (Romania)
Norway Grants – Collaborative Research Projects
The main goal of this project is to evaluate the subsurface geothermal potential of the Baia Mare area, a region that has the highest values of heat flow recorded to date in Romania. This assessment requires a multi-data and multi-disciplinary approach consisting in the evaluation of available data, the collection of modern geoscientific (geological, geochemical, hydrogeological and geophysical) data, and in joint interpretation of this data. The final outcome, 3D lithospheric, hydrogeological and geothermal models, will be used further in geothermal energy exploitation, which will benefit the community from the Baia Mare area, Romania.
Geothermal energy is a renewable source that has little effect on environment. The amount of CO2 emitted during the generation of electrical and thermal energy using this renewable source is very small, close to zero, since no burning process is involved. Our study area is located in the northwestern part of Romania and comprises tens of villages and the town of Baia Mare. In the rural areas, wood is the main source used for space heating. Fossil fuels are also used but into a smaller percentage; these fuels are utilised, mainly, to provide electrical and thermal energy for business and public buildings. As an effect, the measured quantities of CO2 emissions resulted from burning wood and fossil fuel are high. The mining industry from this area also contributes considerably to the air, soil, surface and shallow waters pollution. For decades, this area was an important national source for Pb, Zn, Au, Ag, and Cu, but the mining activity transformed this region into one of Romania’s most polluted with heavy metals mining area. One way to decrease the extreme pollution in this region, in particular the CO2 emissions, is to find a source of green, renewable energy. Measured high heat flow values in this region point towards geological structures with geothermal potential. We therefore propose to undertake a detailed study of the Baia Mare area and to combine geological, geophysical, geochemical and hydrogeological available and new data for assessing its geothermal potential. The project expected results are encouraging since previous geothermal exploration performed in areas located south of Baia Mare showed the efficiency of using the geothermal waters to produce electrical and thermal energy.
In Romania, most of the geothermal reservoirs were identified during surveys performed for hydrocarbon exploration. Until now, focussed geothermal projects were not executed in the Baia Mare area, mainly, because of insufficient financial means. Existing geological, geochemical, hydrogeological and geophysical data can be used in a first stage to create an initial 3D geothermal model. This model will be used to identify subsurface structures which may show high potential for geothermal exploration, as existent heat flow data indicate. Based on the initial assessment, a pilot site will be defined for additional data collection and new geophysical data will be recorded using standard and advanced equipment. Data processing, including various data inversion and modelling, will be performed using commercial and in-house software. 1D temperature models will be obtained based on new temperature data collected from the pilot site. Interpretation of active and passive seismic data will provide information on the subsurface structural geology and the fluid content. Magnetic and magnetotelluric measurements will help to identify subsurface igneous and conductive bodies. Analysis of existing well data (logs) will supply information about the rocks lithology and properties. Modelling will be used to create a hydrodynamic model of the geothermal reservoir. Using hydrogeological data obtained for the pilot area, we will be able to estimate the amount of usable hot waters extracted from the geothermal reservoir.