Annual output energy harvested by building-integrated photovoltaics based on the optimized structure of 2-terminal perovskite/silicon tandem cells under realistic conditions

Under standard test conditions (STC), we attain the optimal simulated efficiency of 30.60% for a 2-terminal perovskite/SHJ tandem solar cell (perovskite's bandgap of 1.67 eV, thickness of 640 nm). Primarily, we found that the optimal perovskite thickness of the tandem solar cell applied to building-integrated photovoltaics (BIPV) under realistic conditions (incident angle of light, solar module temperature, and irradiance intensity and shape) differs from the STC-based optimal perovskite thickness, depending on the incident angle and spectral irradiance shape. The actual optimal configuration of the 2-terminal tandem solar cell is attained at a perovskite thickness thinner than that of the STC-based optimal configuration. This is because the irradiance intensities in the visible and near-infrared light ranges of the 1000-W/m2-normalized actual spectral irradiance are higher and lower than those in corresponding ranges of the AM 1.5 G spectral irradiance, respectively. Consequently, the 2-terminal tandem solar cell based on a perovskite thickness of 500 nm is assumed to be optimal for the BIPV system. The tandem solar cells mounted on the rooftop, the south, east, and west facades achieve the highest annual energy of 270.11, 165.74, 98.50, and 87.64 kWh/m2, the corresponding annual average efficiency of 21.68, 13.31, 7.91, and 7.04%, respectively.