Practical Solutions for Increasing the Albedo of Urban Surfaces to Reduce the Heat Island and Cooling Load of Buildings

Abstract

The increase in temperature of urban areas relative to the surrounding areas, known as the urban heat island (UHI) phenomenon, has become one of the main challenges of metropolises. This phenomenon not only affects the thermal comfort of citizens, but also significantly increases energy consumption by increasing the energy demand for cooling buildings. The search for a solution to this problem naturally depends on the environmental and physical conditions of cities and can be quite different for each region. In this metropolis like Tehran, the research methodology of this paper is based on a systematic review of analytical studies and a descriptive adaptation of strategies for increasing albedo in hot and dry climates. One of the effective and low-cost solutions to reduce this phenomenon is to increase the albedo of urban surfaces through the use of reflective materials. The results show that cool roofs can reduce surface temperatures by up to 6°C and cooling energy consumption by 15–40%, while high-albedo pavements reduce surface temperatures by up to 18°C but may increase the average ambient radiant temperature. Analysis of Tehran’s climate conditions shows that combining reflective strategies with green infrastructure and urban geometry management can lead to significant reductions in thermal loads. Accordingly, a phased framework for implementing albedo-enhancing strategies in urban environments is proposed.