Thermal and Thermoelectric Generation Using Geothermal Energy Extraction Through Cogeneration System

Abstract

The manuscript has focused on the evaluation of the improvement of energy efficiency in using geothermal energy for heat and electricity generation through additional thermoelectric production to conventional heat transfer processes. The proposed system uses Peltier rings made up of a serial and parallel Peltier cells grouping, as part of the upward and downward ducts that connect the geothermal heat exchanger and the surface heating system. The new system can improve performance related to conventional operating mode. As thermoelectric generation does not reduce working fluid temperature significantly, available heating power is preserved, thus improving overall efficiency. The new system operates, therefore, under cogeneration mode, being consistent with energy efficiency principles, which ensures an improvement of system performance related to conventional operating mode. Tested thermodynamic efficiency has been around 50%, which is a very good value if compared to conventional thermal systems. Global efficiency, including mechanical aspects, is reduced to 21.5%, which is comparable to current overall efficiencies of conventional systems. This efficiency is, however, improved up to 26%, if thermoelectric conversion is produced. The system operates at its higher efficiency mode in cold climates where thermoelectric conversion is more effective. Keywords: Cogeneration, efficiency improvement, geothermal energy, thermoelectric conversion Cite this Article Carlos Armenta Deu, Leticia Bottazzi Thermal and Thermoelectric Generation Using Geothermal Energy Extraction Through Cogeneration System Journal of Alternate Energy Sources & Technologies.2020 ; 11(1): 58-71 p.