Polarization management of photonic crystals to achieve synergistic optimization of optical, thermal, and electrical performance of building-integrated photovoltaic glazing

Semitransparent photovoltaics (STPV) provide a promise solution for building integrated photovoltaic glazing and automotive applications. However, current methods to achieve transparency make it difficult for STPV to simultaneously have high light-utilization efficiency and neutral color. Here, we propose a selective polarization transmission approach to achieve transparency of PV by utilizing the polarization-selective property of photonic crystals. And, a multiscale multiphysics theoretical model is developed for accurate analyses of optical, electrical, and thermal performance (average visible transmission AVT, photoelectrical conversion efficiency PCE, light-utilization efficiency LUE and U-value) of the grating photonic crystal (G-PC)-based PV glazing. Based on the polarization-selective property of G-PC, the G-PC based PV glazing can offer PCEs of 19.30%, 14.81%, and 11.75% at the AVTs of 25.10%, 40.11%, and 50.28%, respectively. Moreover, the transmitted light can maintain a neutral color within the variation of the incidence angle from 0 to 60 ̊. The U-value of double-layer G-PC based PV glazing is 3.43 W/m²/K at the ambient temperature of −20 °C, and it can be reduced to 1.21 W/m²/K when air layer thickness increase from 460 nm to 10 mm. Furthermore, based the analyses under real-world conditions, it can be found that the G-PC based PV glazing can offer relatively stable performance over the effective time period.