Approach to the geothermal potential of Colombia

Abstract

The geothermal potential of Colombia was calculated through the volumetric method, by considering the dimensions assigned to the hot springs registered in the national territory, as individual or grouped hot springs (cluster), which were assumed as the possible reservoirs. The calculation was made for two scenarios, depending on the assigned variables. An expected area, a thickness, and a reference temperature of 2 km2, 1.5 km and, the mean surface temperature calculated according to the altitude, respectively, and a maximum recovery factor of 0.25, for the optimistic scenario. An expected area, a thickness, and a reference temperature of 0.785 km2, 1 km, and condenser temperature (40 °C), respectively, and a maximum recovery factor of 0.2 for the pessimistic scenario. In both cases, the reservoir temperature was inferred from the aqueous geothermometers. The 324 hot springs recorded in the national territory were grouped into a total of 165 clusters in the first scenario and, 176 in the second one, distributed in 21 preliminary delimited geothermal areas associated with volcanic systems and 16 Departments, located - outside of the preliminary delimited geothermal areas.In the optimistic scenario, the total electrical power of the 21 geothermal areas distributed in 80 clusters was calculated at 1170.20 ± 31.39 MWe, with a stored heat of 138.60 ± 1.84 EJ. The greatest resources are found in the geothermal areas of San Diego, Santa Rosa, Cerro Machín and Nereidas-Botero Londoño, with electrical powers of 141.85, 137.24, 129.94 and 100.72 MWe, respectively. These are all located in the northern block of the Central Cordillera. To the south are the areas of Caldera del Paletará and Azufral, with electrical powers of 117.96 MWe and 81.9 MWe, respectively. On the other hand, the pessimistic scenario for which 94 clusters were defined, a mean electric power of 263.6 MWe and a mean stored heat of 35.56 EJ, were calculated.In the 16 Departments with 85 clusters of hot springs for the optimistic scenario, the total calculated electrical power and heat were 24.95 ± 2.15 MWe and 49.56 ± 0.75 EJ, respectively. The greatest potential corresponds to the Huila Department in 11 clusters, with 12.09 MWe of electrical power and 7.08 EJ of stored heat. Cundinamarca Department has the largest number of hot springs (50) grouped into 24 clusters, with the greatest amount of heat (15.75 EJ) and a power of 1.99 MWe. In the pessimistic scenario, the total calculated mean electrical power and mean stored heat were 5.73 MWe and 8.76 EJ, respectively.