Assessing the impact of PV facades on neighborhood microclimate, outdoor thermal comfort, and energy efficiency in hot climates, case study of Shiraz

The reciprocal interaction between PV panels' efficiency and the microclimate affects three key factors: solar energy generation, building energy consumption, and urban heat island mitigation. Previous studies have not evaluated the simultaneous effect of different pavement albedos and building-applied PV facades. Hence, this study investigates the thermal interactions between PV facades and various pavement materials to evaluate their impact on a neighborhood microclimate, outdoor thermal comfort, and PV panels' energy efficiency. The scenarios were modeled using ENVI-Met simulation software for a neighborhood district in Shiraz. The results revealed that installing BAPVs causes a maximum decrease of 0.22°C in air temperature compared to the base model. Pavements with higher albedo materials will reduce air temperature and increase relative humidity and universal thermal climate index. In summer, the maximum air temperature reduction is 1.51°C while the increase in UTCI would be 3.45°C. With the higher albedo pavement materials, façade temperatures increase up to 7.62°C in summer reducing PV panels' energy efficiency by 4.83%. The optimal option differs based on design objectives. In summer, light concrete pavement is optimal for improving the neighborhood microclimate, while asphalt pavement is the best choice for outdoor thermal comfort and BAPV energy efficiency. In winter, asphalt pavement is the best option for the neighborhood microclimate, while with outdoor thermal comfort as the target, light concrete pavement is the best. The findings bridge a critical gap in understanding the integrated environmental impacts of pavements and PV panels that contribute to sustainable urban design in similar climates.