The Building's Green, But What About The Commute?

"Designers and builders expend significant effort to ensure that our buildings use as little energy as possible. This is a good thing-and very obvious to anyone who has been involved with green building for any length of time. What is not so obvious is that many buildings are responsible for much more energy use getting people to and from those buildings. That's right-for an average office building in the United States, calculations done by Environmental Building News (EBN) show that commuting by office workers accounts for 30% more energy than the building itself uses. For an average new office building built to code, transportation accounts for more than twice as much energy use as building operation."

"'Transportation energy intensity' is a metric that has long been used to measure such things as how efficiently freight is transported. We're proposing it here as a metric of building performance. The transportation energy intensity of a building is the amount of energy associated with getting people to and from that building, whether they are commuters, shoppers, vendors, or homeowners. The transportation energy intensity of buildings has a lot to do with location. An urban office building that workers can reach by public transit or a hardware store in a dense town center will likely have a significantly lower transportation energy intensity than a suburban office park or a retail establishment in a suburban strip mall."

"In addition to these direct emissions from transportation, there are many other environmental impacts associated with the infrastructure needed to support transportation and with development patterns. Our roadways create impervious surfaces that result in significant pollutant runoff into waterways-in fact, non-point source water pollution from stormwater runoff is now the nation's leading source of water pollution to estuaries and the third largest to lakes. Highways fragment ecosystems and wildlife habitat. Paved areas, including roadways and parking lots, absorb solar energy, contributing to localized heat islands that exacerbate smog and increase air-conditioning requirements in urbanized areas. And stormwater runoff from these surfaces creates thermal pollution that makes many waterways unsuitable for trout and other cold-water fish."