Urban Heat Island and Building Energy Consumption

Abstract

The change of natural land cover to impervious surfaces, dense built forms in cities causes built areas to experience high temperature than surrounding suburbs. This leads to urban heat island phenomenon which affects the microclimate. Despite the various studies supporting the importance of urban fabric, there is still a need to demonstrate how the urban surfaces can impact the temperature of surrounding areas. The purpose of this study is to determine the temperature change due to urban fabric by analyzing the role of materials having different albedo, reflectance and vegetation in changing the air and surface temperatures within a city. Existing case of an institutional campus (State University of Visual and Performing Arts, Rohtak, India) is undertaken for examining the temperature change at different urban surfaces by using the ENVI-met simulation software. The study area is analyzed for two scenarios involving the existing case (EC), proposed case (PC) scenario to understand the impact of different surface materials and vegetation on temperature. Surface and air temperature in both scenarios are extracted at two different heights-pedestrian level and canopy level. It is analyzed that different urban surfaces and construction materials play an effective role in varying the surface temperature and heat island intensities. Result shows potential benefits of increasing the albedo and reflectivity of pavements and roofs inside the city which helps in lowering surface temperature of walls and roofs and also lowering the air temperature around the surfaces. Along with this, vegetation also play an important role by creating a cooler environment by shading and reducing the surfaces temperature of built surfaces in an area. Therefore, adapting to essential urban green strategies can save city’s future from risks of urban heat islands.