Impacts of city-block-scale countermeasures against urban heat-island phenomena upon a buildingÕs energy-consumption for air-conditioning Yukihiro Kikegawa a, * , Yutaka Genchi b , Hiroaki Kondo c , Keisuke Hanaki d a Department of Environmental Systems, Meisei University, 2-1-1 Hodokubo, Hino-shi, Tokyo 191-8506, Japan b Research Center for Life Cycle Assessment, National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan c Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan d Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan Available online 27 July 2005 Abstract This study quantifies the possible impacts of urban heat-island countermeasures upon buildingsÕ energy use during summer in Tokyo metropolis. Considering the dependency of the buildings air temperature upon the local urban canopy structure, Tokyo urban canopies were classified in the city-block-scale using the sky-view factor (svf). Then, a multi-scale model system describing the interaction between buildingsÕ energy use and urban meteorological con- ditions was applied to each classified canopy. In terms of urban warming alleviation and cooling energy saving, simulations suggested that the reduction in the air-conditioning anthropogenic heat could be the most effective mea- sure in office buildingsÕ canopies, and that vegetative fraction increase on the side walls of buildings in residential canopies. Both measures indicated daily and spatially averaged decreases in near-ground summer air temperature of 0.2–1.2 °C. The simulations also sug- 0306-2619/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.apenergy.2005.06.001 * Corresponding author. Tel.: +81 42 591 6215; fax: +81 42 591 6196. E-mail address: kikegawa@es.meisei-u.ac.jp (Y. Kikegawa). Applied Energy 83 (2006) 649–668 www.elsevier.com/locate/apenergy APPLIED ENERGY