Experimental study on a solar thermoelectric power generation system under non-uniform irradiation

Abstract

Non-uniform irradiation caused by high light concentration significantly affects the performance of the solar thermoelectric power generation system, but the research remains at the theoretical stage. This paper establishes an experimental setup for the solar thermoelectric system and conducts a comprehensive experimental study of the system operating under non-uniform irradiation. The temperature, power and efficiency of the systems are tested for different input powers, cooling methods and structures, and irradiation uniformity. The results indicate that the output power of the solar thermoelectric system slightly increases and then decreases as the irradiation uniformity increases. The system’s output power is minimized when the irradiation uniformity approaches 100%. The optimum irradiation uniformity of the solar thermoelectric system is 47.4% and the maximum efficiency is 1.495%, which is an improvement of 7.6% compared to the efficiency of 98.4% irradiation uniformity. The performance of the solar thermoelectric system can be further improved by using a double-layer TE structure. At a concentration ratio of only 12.4, the double-layer system connected in series achieved a maximum efficiency of 2.06%, which is 0.55% higher than the single-layer system. The importance of optimizing irradiation uniformity to improve system performance is experimentally revealed. These results are important for clarifying the operating principle of the solar thermoelectric system under non-uniform irradiation and can guide the subsequent design of high-efficiency solar thermoelectric systems.