Inverse Design of Wavelength-Selective Film Emitter for Solar Thermal Photovoltaic System

Solar photovoltaic (PV) technology is developing quickly due to the continual rise in demand for energy and environmental protection. Solar thermal photovoltaic (STPV) systems can break the Shockley–Queisser limit of conventional PV systems by reshaping the solar spectrum using selective absorbers and emitters. However, the traditional design method relies on the designer’s experience, which fails to achieve rapid designing of STPV devices and greatly improve the performance. In this paper, an STPV thin-film selective emitter is inversely designed based on a genetic algorithm. The optimized structure consists of SiO2 and SiC layers alternately stacked on a Cr substrate, whose emissivity can reach 0.99 at 1.86 μm. When combined with an InGaAsSb cell, the power conversion efficiency can be up to 43.3% at 1673 K. This straightforward and easily scalable film emitter can be designed quickly and gain excellent efficiency, which promotes the practical application of STPV systems.