¿WHAT IS GEOTHERMAL ENERGY?
Geothermal energy is that which is contained in the form of heat in the interior of the Earth. (Barbier, 1997) This includes both the heat stored in solid rock as the fluids that found in the pores. (Clauser, 2006)
The origin of this heat is associated with physical processes and the structure of the planet, since the heat that lies in the materials that make up the core and the mantle is gradually transmitted to the cortex generating an upward flow that through and reach the Earth's surface is lifted in the atmosphere; This is evidenced by an increase of the temperature of the rocks with depth, proving that there is a geothermal gradient, where the temperature rise 3° C every 100 meters of depth. (Barbier, 1997) (Pous & Jutglar, 2004)
In the field of contact crust-mantle, there are some areas that due to it’s geological configuration allow the flow of rising crust be more intense than in the other remaining areas. These "hot" areas are usually found in continental oceanic funds of high volcanic and seismic activity. (Pous & Jutglar, 2004)
The extraction and use of heat requires a carrier in this case geothermal fluids to transfer this flow to the Earth's surface. Heat is transferred from the hot water or steam in hydrothermal aquifers through conduction and then by convection. (Pous & Jutglar, 2004) (Barbier, 1997)
GEOTHERMAL ENERGY IN COLOMBIA
With respect to the geothermal resource, Colombia has a privileged position, since it is located in the ring of fire of the Pacific area where the natural subsurface temperature gradient is high, demonstrating volcanic activity that is linked in the same way by the subduction of plate Nazca under the South America plate. Currently evidenced this potential in areas surrounding volcanoes Chiles, Cerro Negro, Cumbal, Azufral, Galeras, Doña Juana, Sotará, Nevado del Huila, Nevado del Ruiz and Nevado del Tolima. (Marzolf, 2007)
Nevertheless Colombia supplements their energy needs, through the hydroelectric and thermoelectric generation, without energy from geothermal energy despite multiple studies that have been done. (Marzolf, 2007)