Photovoltaic road pavements as a strategy for low-carbon urban infrastructures.

Urban Heat Islands (UHIs) are expanding in anthropized areas, causing serious climatic consequences such as rising temperatures and citizens' discomfort. Several studies have identified and confirmed how the use of cool road pavements can mitigate and reduce the negative effects of UHIs. This study performs a microclimate simulation of San Pietro in Vincula Square in Rome through ENVI-Met software by replacing the current asphalt pavement in the parking area with a cool one. The proposed layout consists of light concrete pavers in the parking lots, parking aisles made of photovoltaic (PV) panels, and a perimeter hedge. The innovative use of PVs is analysed from the thermal and economic viewpoints alike. In the first case, its thermal characteristics like those of asphalt provide results in terms of air temperature, mean radiant temperature, and predicted mean vote close to the current ones. Furthermore, the energy analysis shows the PV's effectiveness in terms of economic impact. Indeed, the electricity produced by the proposed PV system is enough to light the area, and its surplus can power public activities such as electric vehicle charging. The initial investment would pay for itself in the 25-year service life as confirmed by the positive net present value (NPV), and the cash flow reveals a break-even point in the 15th year.