Full spectrum photon management of photonic crystal-based aerogels to achieve the multiscale multiphysics regulations and optimizations of PV-TE/T systems

Abstract

Multicomponent coupling is an effective way to achieve full-spectrum solar energy utilization. However, conventional multicomponent coupled PV systems are deficient in the rational distribution of full-spectrum sunlight. In this study, a photovoltaic-thermoelectric/thermal (PV-TE/T) system with photonic crystal-based aerogels (PCA) is proposed based on a novel strategy for efficient full-spectrum solar energy utilization. Then, a multiscale multiphysics theoretical model is developed to study the effects of full-spectrum selectivity characteristics of PCA on the performance of the PCA-based PV-TE/T system. Comparative analyses between stand-alone PV system, tandem PV-TE system, normal PV-TE/T system and PCA-based PV-TE/T system are performed. The full-spectrum selectivity characteristics of PCA allows the PCA-based PV-TE/T system to not only increase the maximum achievable photon current density of PV component by 2.39%–3.00%, but also to increase the heat source (light absorption) for TE component by at least 2609.84%. When the concentration increases to 20, the electrical efficiency of the stand-alone PV system is already 0%, and the electrical efficiency of the tandem PV-TE starts to decrease to 27.01%. As for the PCA-based PV-TE/T system, the maximum electrical efficiency of the PCA-based PV-TE/T system is 32.64% at the concentration of 93. Meanwhile, the thermal collector of the PCA-based PV-TE/T system absorbs 6277.5 W/m2 of thermal energy. Therefore, the PCA-based PV-TE/T system not only has a high efficiency of full-spectrum solar energy utilization, but also is applicable to higher concentrations, which offers the system the potential for further cost reductions.