MB Civic

By DAN MITCHELL

KARL T. ULRICH, a professor at the Wharton School of the University of Pennsylvania, has put forth a provocative theory. Traveling by bicycle, he argued in a recent paper, may cause more environmental harm than driving around in pollution-spewing, fossil-fuel-swallowing cars and sport utility vehicles.

How can this be? Bicyclists are healthier, he wrote, so they live longer. Over their lifetimes, they consume more energy than they save.

Among the “holes in this argument that you can drive a biodiesel-powered Hummer through,” wrote Andrew Leonard, in his blog How the World Works, at Salon.com, is that bicyclists in general are naturally inclined to be responsible consumers of energy, and more enlightened when it comes to environmental issues.

“I see it happen here in Berkeley all the time,” Mr. Leonard wrote. “First you start biking around town, then you put solar panels on your roof and start worm composting your newspapers. Suddenly, you find yourself raising organic free-range chickens in your backyard and hosting weekly meetings of your local Peak Oil Awareness encounter group.”

Mr. Ulrich’s paper is based on a huge set of loose assumptions about the effects of exercise on life span and the impact of longevity on energy use. But it isn’t as purposely confrontational as it may sound. Mr. Ulrich is himself a bicyclist, and he applauds those who ride bicycles. And there’s no arguing with the underlying logic he employs: living longer means you use more energy. That problem is one that will soon be popping up in all kinds of unexpected ways. “Indeed,” he wrote, “the greatest environmental peril society may face is the looming prospect of slowing the aging process.”