Addressing global climate change and achieving carbon neutrality as soon as possible is a common aspiration for all of humanity. In this context, the development of refrigeration technology is undergoing a significant transformation. This paper proposes a composite system that integrates sky radiation cooling technology with solar thermal power collectors. Through the analysis of experimental data, it is indicated that the sky radiative cooling technology can significantly enhance the overall energy efficiency of the solar thermoelectric system. With this combination, not only the power generation efficiency of the solar thermal collector and generator is improved, but also the deficiency that the solar thermal collector and generator can only operate during the day and be idle at night is effectively compensated for, thereby reinforcing the sustainability of energy utilization. The analysis shows that sky radiation cooling technology has a significant effect on optimizing the utilization of solar thermal electricity.