Developing a novel solar-driven cool pavement to improve the urban microclimate

Abstract

The thermal properties of pavement play a significant role in raising urban temperatures and creating urban heat islands (UHI). This phenomenon leads to increased energy consumption in buildings and reduces the thermal comfort of outdoor urban spaces. A standard modest application of thermoelectricity has been limited to indoor use to cool or heat buildings and outdoor use to harvest energy from asphalt. While the application of thermoelectric technology to cool the outdoor environment is rare, a novel solar-driven pavement thermoelectric system (SDPTES) has been developed to use solar energy in combination with rainwater and/or graywater to decrease the outdoor ambient air temperature and improve the urban microclimate. An SDPTES prototype was fabricated to verify the cooling capacity based on outdoor tests in the hot climate of Cairo. The study found that the application of SDPTES led to a reduction in pavement surface temperature of 14.1° C compared to conventional concrete mosaic pavement. These results represent a starting point for the development and application of thermoelectric paving technology for outdoor cooling purposes.