Energy yield of bifacial textured perovskite/silicon tandem photovoltaic modules

Bifacial perovskite/crystalline silicon (c-Si) tandem photovoltaic (PV) modules that harvest albedo radiation are a promising strategy to further enhance the energy yield (EY) of monofacial perovskite/c-Si tandem PV modules. Given the required current matching in bifacial perovskite/c-Si two-terminal (2T) tandem PV modules, predicting the expected enhancement in EY requires an advanced EY modelling framework. In this study, the architecture, module tilt, perovskite absorber layer thickness, and bandgap of the perovskite top solar cell are optimized for several types of grounds and two locations. Compared to bifacial c-Si single junction PV modules, the relative enhancement in EY of textured bifacial perovskite/c-Si 2T tandem PV modules is around 24-38% for an exemplary grass ground (mean albedo = 35%). With increasing albedo, the optimum bandgap of the perovskite top solar cell decreases from 1.72 eV (black ground, mean albedo = 0%) to 1.55 eV (snow, mean albedo = 88%). This is attributed to enhanced current generation only in the c-Si bottom solar cell due to albedo radiation, entering the solar cell at the rear side. In addition, minor optical losses due to ground shading are found for modules with a finite mounting height in the range of 1 m. Overall, our study highlights the importance of EY modelling to assess the performance of bifacial perovskite/c-Si tandem PV. It provides direction for the design of bifacial perovskite/c-Si tandem solar cells with regard to the device architecture and the choice of the perovskite material with regard to its bandgap.