Geothermal Power Generation Using Thermoelectric Effect

Abstract

Most of the current geothermal power generation technologies transfer thermal energy to mechanical work and then to electricity. In this study, a direct heat to electricity (DHE) technology, without going through mechanical energy, was used to harvest low enthalpy geothermal work. A power generation system has been built using thermoelectric generator (TEG) modules. Experiments have been conducted to measure the output power at under various conditions such as variable temperature differences. TEG modules manufactured with different materials have also been tested. The power generator had an installed power of 500 W at a temperature of around 200oC. An output power of over 160W has been generated with a temperature difference of 80oC. The power generated by the thermoelectric system is almost directly proportional to the temperature difference between the hot and the cold sides. The cost of the DHE power generator is close to that of photovoltaics (PV) in terms of equivalent energy generated.