Countermeasures to Urban Heat Island Considering Urban Energy Usage

In this chapter, we focus on energy use in cities and consider measures to combat the heat island effect, which is a warming factor characteristic of cities. In the introduction, we discuss the general trend of increasing urban populations and energy consumption in developing countries within tropical and subtropical regions, and define the heat island effect, which will intensify in these regions in future. Next, we explain the characteristics, causes, impacts, and countermeasures of this phenomenon, using the severe heat island in Tokyo as an example, with the aim of developing guidelines for tackling this issue in developing countries. In addition, we use several evaluation case studies to discuss heat island mitigation measures incorporating life-cycle assessments. Finally, we consider high-efficiency energy utilization technology that contributes toward both climate change mitigation (CO2 reduction) and adaptation (improvement of the thermal environment), and determine the characteristics of each effect through a comparison with general heat island countermeasures such as greening.