Experimental and theoretical analysis of thermoelectric energy generating system collecting concentrated solar energy

Abstract

ABSTRACT In this study, the electrical energy production limits of a thermoelectric generator in a system providing high thermal efficiency were investigated. Linear Fresnel lenses and solar glass tubes were used as solar concentrator and collector in the system. In order to achieve maximum efficiency from solar radiation, one-axis and two-axis solar tracking systems were used. Experimental measurements were performed for both one-axis and two-axis solar tracking systems at the location 41 14’ N and 36 26’ E. In addition to the experimental study, a numerical model consisting of TEG (Thermoelectric Generator) and cooling system was also developed. The values of parameters such as open-circuit voltage, wind speed, temperature, solar irradiance were collected during the experiments. Pure water and acetone were used as working fluids in the heat pipes in the system. As a result of all these processes, the maximum open-circuit voltage values obtained in the thermoelectric generator mounted on the head of the heat pipe were determined as 3.45 Volt for pure water and 3.03 Volt for acetone, respectively. The numerical model was validated according to cold side temperature and open-circuit voltage obtained from twelve experimental cases performed on different dates. Cold side temperature and open-circuit voltage at the hot surface temperature of 144.2℃, the highest temperature among these experimental cases, were calculated as 2.95 V and 93.14℃, respectively. In this case, the error between the numerical and experimental results was 7.5% for the open-circuit voltage and 4.5% for the cold side temperature. As a result, it was seen that the experimental measurements and the numerical results were in good agreement.