Thermoelectric System Based on Integrated Solar Concentration and Storage as Well as Radiative Cooling for All-Day Power Generation

Abstract

Thermoelectric power generation is an environmentally-friendly method of generating electricity that has the potential to save energy consumption. However, previous studies could not realize all-day power generation due to the inability to collect solar energy at nighttime. Furthermore, heat concentration and storage are not simultaneously achieved at daytime. In this study, we propose a new thermoelectric system combining an integrated radiative cooling device with solar concentration and storage to realize efficient all-day power generation. By introducing solar collector and greenhouse cavity, more solar heat can be concentrated and stored at the hot end of the thermoelectric generator (TEG), while the integrated radiative cooling unit further reduces the temperature at its cold end. This combination results in a larger temperature difference, significantly enhancing output voltage. Radiative cooling also creates a temperature difference between the two ends of the TEG at nighttime, allowing continuous power generation. Eight-day outdoor experiment demonstrates that, on clear and cloudy days, the maximum temperature difference reaches 160°C and 12.4°C, with output voltages of 1420mV and 151.8mV. The 24-hour average output voltages also reach 84.1mV and 36.2mV. Notably, even during nighttime with high humidity and low temperatures, the voltage output can reach 15.6 mV. This innovative TEG system provides a viable strategy for powering small devices in remote areas.

Keywords: Thermoelectric generator, Solar energy, Radiative cooling, All-day power generation, Solar storage