A review on hygrothermal transfer behavior and optimal design of building greenery with integrated photovoltaic systems

In the context of urban heat island effect and carbon–neutral goal, building greenery with integrated photovoltaic (BGIPV) systems provide multiple benefits for sustainable urban development and received more and more attention as an innovative building skin solution in recent years. This review first outlined the historic evolution of BGIPV system, tracing its journey from initial conceptualization and technological research to practical application. And then the hygrothermal transfer behavior of BGIPV system were comprehensively examined from the following three aspects: 1) hygrothermal environment and vegetation condition of greenery systems, 2) photovoltaic power generation efficiency, and 3) water balance of systems. Subsequently, the energy balance and the commonly used thermal performance simulation models for BGIPV system were analyzed and compared. Considering the synergistic effect between PV and vegetation, a summary of the performance optimization studies for BGIPV system was also provided. And it can be found that the thermal interaction between photovoltaic modules and vegetation exhibits dynamic variations under different climatic and spatial configuration conditions, leading to uncertainties in the overall performance of BGIPV systems. Therefore, the interaction mechanism between photovoltaic modules and vegetation should be further clarified for the accurate performance prediction and design optimization. Finally, prospects were proposed from different aspects, aiming to provide reference for future research and development of BGIPV systems.