High-efficiency dynamic lossless coupling of a spectrum splitting photovoltaic-thermoelectric system

Photovoltaic and thermoelectric devices are commonly electrically separated in the spectrum splitting photovoltaic-thermoelectric (SSPV-TE) system because of their distinct output characteristics, resulting in increased system investment and hindering practical application. In this paper, the concept of high-efficiency dynamic lossless coupling of the SSPV-TE system is proposed. A novel electrical-thermal co-design method is provided to achieve high-efficiency dynamic lossless coupling of the SSPV-TE system. The economics of both the electrically separated and series lossless coupling systems are also evaluated. The results indicate that matching the maximum power current of the photovoltaic and thermoelectric devices and weakening the thermoelectric Peltier effect are effective ways to achieve the series lossless coupling. With the electrical-thermal co-design, the hot end of the thermoelectric devices can operate at the allowable temperature of 800 K, and the power difference between the electrically separated and series systems is less than 4 mW. The series system achieves the same average power and efficiency of 1.03 W and 22.48% as the electrically separated system under one-day varying solar irradiation, demonstrating that the high-efficiency dynamic lossless coupling is achieved. The cost of the series system is 4.75 $/W, while that of the electrically separated system is 5.29 $/W. The cost of the SSPV-TE system can be reduced by 10.21% by implementing the series dynamic lossless coupling.

Automated summary

A concept of high-efficiency dynamic lossless coupling of the spectrum splitting photovoltaic-thermoelectric (SSPV-TE) system is proposed in this paper. A novel electrical-thermal co-design method is provided to achieve this high-efficiency dynamic lossless coupling. The results demonstrate that the series system achieves the same average power and efficiency as the electrically separated system, indicating the achievement of high-efficiency dynamic lossless coupling.