Harvesting heat energy using geothermal and hydronic pavements for sustainable cities: A comprehensive review of an emerging idea

Abstract

To minimize the environmental and ecological impacts of non-renewable energy sources, a massive switch to solar, geothermal, wind, and other renewable energy sources are necessary. Energy harvesting pavements are being widely explored as solar energy is the most abundant source of energy on Earth and 20 to 30% of the urban area is covered by road pavements which are continuously exposed to solar radiation. One of the feasible methods to harvest heat energy from pavements is to collect and transfer heat using a network of fluid pipes embedded in the pavement. It will reduce the pavement temperature during summer and the stored heat energy can be used to melt snow/ice from the pavements during winter. Apart from the conservation of non-renewable energy, these pavements also contribute to urban heat island (UHI) mitigation, extension in pavement life, and provide a smooth riding surface in winter. This paper provides an extensive review of these pipe-pavement energy harvesting systems in terms of the factors affecting their design, impact on thermal performance, construction and economic feasibility of the system. The paper also highlights the scope for further research in this area that will help in improving the efficiency of this system. � 2023 Elsevier Ltd