Optimum Thermal Concentration of Solar Thermoelectric Generators (STEG) in Realistic Meteorological Condition

Abstract

Global warming and air pollution concerns make renewable energies inevitable. Thermoelectric (TE) generators—solid-state devices which can convert thermal energy into electricity—are one of the candidates to capture the energy of the sun’s rays. Impact of high thermal on flat panel Solar Thermoelectric Generator (STEG) performance is known. In this research, a method to optimize thermal concentration in realistic terrestrial condition is introduced. To this end, a Simulink model of the STEG was developed, and module performance curves are determined. According to the results, Thermal concentration in realistic condition is more than double, compared to standard condition. The efficiency of the STEG was 4.5%, 6.8%, and 7.7% when the module figure of merit (ZT) was set to 0.8, 1.2, and 1.5, respectively, in locations with a higher ratio of diffused radiation (e.g., Aalborg and Denmark). These values corresponded to 70%, 106%, and 121% of the electrical power produced by parabolic troughs under the same meteorological condition. Furthermore, the possibility of controlling the ratio of heat and electricity in the cogeneration system is possible by controlling the heating flow or electric current. Heating flow can be controlled by the electrical current in STEG over 17 percent of its value in optimum condition.

Keywords

• solar thermoelectric generator
• optimization
• cogeneration
• thermal concentration