Impacts of urbanization on urban structures and energy demand: What can we learn for urban energy planning and urbanization management?

Since 2007, for the first time in human history, more than half of the world's population has been living in cities. The urbanization process is a key phenomenon of economic development, and leads to a significant concentration of human resources, economic activities, and resource consumption in cities. Although covering only about 2% of the earth's surface, cities are responsible for about 75% of the world's consumption of resources. This trend will intensify over the next decades as a consequence of high urbanization rates in Africa and, even more importantly, in Asia. In order to estimate the impact of urbanization on energy demand, we have to identify the different processes and mechanisms of urbanization that substantially affect urban structures as well as human behavior. Taking a closer look at city-related production, mobility and transport, infrastructure and urban density, as well as private households, we find that various mechanisms of urbanization within the different sectors of the economy lead to a substantial increase in urban energy demand and to a change in the fuel mix. The relevance of these mechanisms differs considerably between developed and developing countries as well as within the group of developing countries. Over the next decades, cities and especially newly emerging megacities in developing countries will play a key role concerning the development and distribution of global energy demand. Hence, urban energy planning and urbanization management will be pivotal for creating the right framework conditions for a sustainable energy future. (C) 2010 Elsevier B.V. All rights reserved.