Chapter 5: Energizing Cities

State of the World 2007 - Our Urban Future
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-Janet L. Sawin and Kristen Hughes

The Industrial Revolution happened in the blink of an eye. In the span of a few generations, cities were transformed from dense areas of narrow streets with small, low dwellings to skyscrapers and sprawling suburbs. Energy use surged as well, and the advent of the fossil fuel age, which provided power for elevators, electric lights, and motor vehicles, enabled cities to become what they are today.

Cities require energy to build infrastructure, to manufacture goods, to transport people, to prepare food, and to light, heat, and cool buildings. The infrastructure itself, including streets, buildings, bridges, and other urban features, represents large quantities of embodied energy—the energy invested in these structures during their lifetimes from the cradle of raw materials, to city block, to eventual grave. Urban residents also consume large amounts of energy indirectly in the food and other goods they import.

Today, cities have an unprecedented opportunity to change the way they supply and use energy. New eco-cities such as Dongtan in China may show the way, even as existing cities turn to technologies rooted in the past—from adobe architecture to passive solar heating. When complemented by conservation, more-efficient technologies, and new decentralized, small-scale energy services, these efforts can help cities confidently navigate the forthcoming peak of cheap oil and natural gas production while reducing the impacts of climate change.

Janet Sawin is a Senior Researcher and Director of the Energy and Climate Change Program at the Worldwatch Institute. Kristen Hughes is a research associate and doctoral candidate at the Center for Energy and Environmental Policy, University of Delaware.