Mitigation of Urban Heat Risks via Shading Stations: An Experimental Comparison of Fabric and Photovoltaic Shading

Exploring mitigation solutions is important for supporting heat-resilient urban designs. Shading stations offer a practical means of blocking direct solar exposure and improving the thermal environment of the station. This study aimed to compare the heat mitigation performance of fabric and photovoltaic (PV) canopy shading in terms of microclimate regulation and outdoor thermal comfort improvement based on field experiments in subtropical Jiangsu, China. The results indicate that artificial shading could significantly reduce the universal thermal climate index (UTCI), with average daytime reductions of 3.5°C for fabric shading and 3.1°C for PV canopy shading. Although both types of shading stations were effective, they exhibited distinct mechanisms of action. Fabric shading provided more consistent cooling and radiation reduction at the ground level (0-0.5 m). During the full-shading period (10:30-13:30), PV shading showed stronger downward longwave radiation, resulting in a weaker mitigation performance at pedestrian height (1.0-1.5 m) than that of fabric shading. Furthermore, the shading-induced mitigation performance can be affected by underlying surfaces. Grass surfaces enhanced cooling via evapotranspiration, whereas high-albedo hard surfaces sometimes contributed to heat accumulation. The differences in vertical temperatures verified the different mitigation mechanisms of the two types of shading stations along their height. Overall, this study provides a reference for designing artificial shading.