OIL AND GAS INDUSTRY GOING GREEN: GEOTHERMAL ENERGY GENERATION FROM PETROLEUM RESERVOIRS

Geothermal resources are renewable sources of energy with very attractive features. Well designed geothermal systems allow constant electricity generation over time, free of pollutants emission and independent of seasonal variations and weather changes, among other benefits. However, the growth rate of the geothermal industry during the last years has not been as high as expected, mostly due to existing uncertainties and high initial investments that question the technical and economical feasibility of geothermal projects. This work compiles and analyzes information about non conventional possibilities for the generation of geothermal energy associated with petroleum reservoirs, given that the possible utilization of existing oil and gas infrastructure and facilities as part of the geothermal energy generation process would significantly decrease both initial and operational expenses, and then significantly reduce risks associated. Three different cases of geothermal energy generation associated with petroleum reservoirs were identified, explained and exemplified through literature review and gathering of previous research reports available: 1. Generating low enthalpy geothermal energy from co-produced hot water from oil fields (this applies for deep reservoirs with a high bottom hole temperature or fields where steam injection or hot water stimulation processes have been applied for a certain amount of time). 2. Producing low enthalpy geothermal energy from abandoned oil and gas wells. 3. Converting a hydrocarbon reservoir to be abandoned into an artificial enhanced geothermal system by oxidizing residual oil through air injection. Later, an early screening criteria for each of the cases is proposed.