Share this story
Close X
Switch to Desktop Site

How white roofs shine bright green

Next Previous

Page 2 of 5

About these ads

Put another way, boosting how much urban rooftops reflect, called albedo (al-BEE-doh) in scientific terms, would be a one-time carbon-offset equivalent to preventing 44 billion tons of CO2 from entering the atmosphere, Akbari says. It’s about the same as taking all the earth’s automobiles off the road for 11 years, the study’s authors say.

“What we have done are very simple calculations,” Akbari says, “but it is novel because, for the first time, we’re equating the value of reflective roof surfaces and CO2 reduction. This does not make the problem of global warming go away. But we can buy ourselves some time.”

Selling the idea
Geoengineers have had similar ideas: covering the Sahara with enormous sheets of white plastic, for instance, or painting the Black Hills of South Dakota white.

But because white roofs create an additional 20 percent energy savings by cutting cooling costs, some say this built-in financial incentive should propel urban rooftops around the globe to lighten up.

“Now that we know what a great help it is on climate change, we expect more utilities to give incentives for homeowners who go entirely white with their roofing material, not just ‘cool’ colors [like pastel blues, reds, and greens]” says Arthur Rosenfeld, a member of the five-person California Energy Commission.

Next Previous

Page 2 of 5

Follow Stories Like This
Get the Monitor stories you care about delivered to your inbox.