Dielectric/metal/dielectric selective reflector for improved energy efficiency of building integrated bifacial c-Si photovoltaic modules

Crystalline silicon bifacial photovoltaic modules (BFPVs), which simultaneously harvest the front- and rear-incident light, are suitable for building-integrated energy harvesting system due to their high power output and transparency. However, the lack of a rear reflector in semi-transparent BFPVs lowers their efficiency. In this study, we proposed a selective reflector (SR) with a dielectric/metal/dielectric structure to increase the power output of BFPVs and ensure a clear view through the BFPV windows. The SRs exhibit a high transmittance in the visible-light region and a high reflectance in the near-infrared (NIR)-light region. By recycling unabsorbed photons by SR, the power output of the SR-incorporated BFPVs is 13.2% higher than that of the BFPVs with bare glass. Moreover, the SR prevents the heating of the interior of buildings by reflecting the NIR light. Hence, the SR can contribute to energy efficiency of buildings.