Regional analysis on the thermal and electrical properties of semi-transparent photovoltaic facades

To accelerate the decarbonization of buildings, semi-transparent photovoltaic (STPV) facade systems, capable of simultaneous power generation and solar regulation, have emerged as a promising solution in building-integrated photovoltaics (BIPV). This study develops a transient coupled optical-thermal-electrical model to comprehensively evaluate the performance of two commercially available STPV facades, with etching ratios of 40% and 20%, across 371 representative cities in China. Simulations incorporate real meteorological data and account for solar radiation transmittance, radiative cooling, convective heat transfer, and power generation. Results reveal that both thermal and electrical behaviors of STPV facades are highly climate-dependent. High-altitude and high-irradiance regions, such as the Qinghai-Tibet Plateau, demonstrate superior electricity output and radiative cooling performance, while low-latitude, humid areas like the Sichuan Basin show relatively poor performance. Importantly, for both STPV facades, secondary solar heat gain accounts for over 50% of total solar heat gain, with radiative transfer as the dominant mode. These findings highlight the importance of indoor-side radiative heat management to optimize building energy efficiency.