Potential benefit of photovoltaic pavement for mitigation of urban heat island effect

Abstract

Pavements in roadway and parking lots occupy large urban areas and contribute to the development of urban heat island (UHI). Photovoltaic (PV) pavement can use PV panels on conventional asphalt concrete (AC) pavement to harvest solar energy at light traffic conditions. This study aimed to evaluate the potential benefit of PV pavement to mitigate UHI effect. First, the heat transfer models for AC and PV pavements were developed. The pavement surface temperature and heat output from pavement surface to near-surface environment were then calculated that were used as the indicator of pavement contribution to UHI effect. A parametric study was conducted to analyze the influences of front glass and wind speed on thermal performance of PV pavement. Varying the thickness and transmittance of front glass have shown noticeable influences on pavement temperature, while the change of heat output is limited. Although the increase of average wind speed results in lower pavement temperatures, the heat output experiences slightly increase. The comparison of PV pavement and conventional AC pavement shows that PV pavement can decrease surface temperature by 3–5 °C in summer and generate 11–12% less heat output at various climate conditions.