Laboratory and Field Tests of Thermoelectric Generators for Power Generation Under Different Conditions

Abstract

Most of the current commercialized thermal, including geothermal, power-generation technologies convert thermal energy to electric energy indirectly, that is, making mechanical work before producing electricity. Technology using thermoelectric generators (TEG), however, can transform thermal energy into electricity directly by using the Seebeck effect. TEG technology has many advantages such as compactness, quietness, and reliability because there are no moving parts. One of the great challenges for TEG to be used for power generation is large-scale utilization. It is difficult to manufacture a TEG system even at the scale of a few kilowatts (kW). To this end, we designed a five-layer TEG apparatus that can be installed with modularized units. Such a system with a layered structure could be expanded in power, something similar to solar photovoltaics (PV). In this study, laboratory experiments were conducted to measure the power output at different flow rates of water, different temperature, and different temperature differences between hot and cold sides. The five-layer TEG device could generate about 45.7 W electricity with a temperature difference of 72.2°C between cold and hot sides. The power of each module was about 0.51 W at this temperature difference. The experimental data can be applied to the design of commercial TEG systems. Finally we tested the TEG apparatus at a geothermal well.