City form as driver of energy consumption and greenhouse gas emissions
November 30th, 2009 by Jim JustThe urban structure of our cities, towns and suburbs is one of the largest drivers of energy consumption and greenhouse gas emissions. Cities that are compact, walkable, and transit-served, with a good distribution of daily services, use a fraction of the energy and generate a fraction of the greenhouse gases as U.S. cities.
There is an enormous difference in energy use between compact cities and sprawling cities, as American ones tend to be – with no corresponding difference in quality of life. This chart shows gasoline use.Vehicle Miles Traveled (VTM) is just part of the story. Other sources of emissions from urban form in the five key categories of infrastructure, and its embodied and operating energy; other advantages of “location efficiency,” including additional benefits of walking; optimized size, orientation and urban shaping of buildings; lost ecosystem services; and behavioral factors and “induced demand” may add up to twice as much as emissions from personal transportation and VMTs alone.
Michael Mehaffy explores each of these factors in depth in an article at Planetizen. Bottom line: increasing urban energy efficiency and cutting urban emissions is about a lot more than increasing density, reducing VMT, and improving fuel mileage. The way we design the places we live can make it improbable or even impossible to reduce energy consumption and greenhouse gas emissions. But if done right, the places we live can make it possible an elegant, satisfying, low-carbon way of life.