Comprehensive research on a high performance solar and radiative cooling driving thermoelectric generator system with concentration for passive power generation

In this paper, to solve the problem that the power generation of currently developed all-day radiative cooling driving thermoelectric generator (RC-TEG) devices is very small, a promising concentrating RC-TEG (C-RC-TEG) device was demonstrated based on high radiation and thermal concentration. The experimental prototype was established, using the local effect of solar energy and radiative cooling to generate relatively high temperature difference driving the TEG to generate electricity. Outdoor experimental results show that the maximum temperature difference is about 4.5 degrees C and the maximum open-circuit is about 56 mV. Meanwhile, we use the established mathematical model verified by experiments to deeply explore the factors affecting its efficiency. The simulation results show solar irradiance and radiative cooling area have a positive effect on the C-RC-TEG model. As the wind speed increases, the power generation of C-RC-TEG drops from 8.58 mW to 6.96 mW. The maximum power generation and temperature difference can be up to 47 mW and 7 K by concentrator in the area of light focusing of 0.003 m2. The results indicate concentrating contributes to the improvement of RC-TEG performance. Our work provides a promising new way of comprehensive guidance on achieving effective conversion of solar energy and radiative cooling into electricity.

Automated summary

To solve the problem of low power generation in currently developed RC-TEG devices, this paper demonstrated a promising C-RC-TEG device based on high radiation and thermal concentration. The experimental prototype utilized solar energy and radiative cooling to generate a temperature difference for driving TEG electricity generation. Results showed that solar irradiance and radiative cooling area had a positive effect on the C-RC-TEG model. Additionally, wind speed was found to decrease power generation. Concentrator in the light focusing area achieved a maximum power generation of 47 mW and a temperature difference of 7 K. This work provides guidance on effectively converting solar energy and radiative cooling into electricity.