If you want to cut back on your energy costs at home – here’s a tip: get a white roof! According to the New York Times, experts say it’s not only an energy saver - but also a way to help cool the planet. Jon and Kim Waldrep of Sacramento discovered the benefits when they bought a plasticized white covering for their roof. They said that in the summer, their house would get to a stifling 115 degrees – and they were running the air conditioner constantly. Since installing the roof covering, their house stays at 80 degrees, even when the temperature outside hits triple-digits. They’ve also reduced their electric bills by an impressive 10%.

Art Rosenfeld is a member of the California Energy Commission who’s been campaigning for what he calls “cool roofs” since the 1980s. He claims that turning all of the world’s roofs “light” over the next 20 years could save the equivalent of 24 billion metric tons in carbon dioxide emissions. That’s what the whole world emitted in 2008. So in a sense, Rosenfeld says it would be like turning off the world for a year. It’s basic physics. Lighter colors reflect back a good portion of the sun’s light and heat, which helps keep a building - and more broadly, the city and the Earth — cooler. These white roofs reduce air-conditioning costs by 20% or more in hot weather. Officials in places like Dubai and Japan have embraced the idea of reflective roofs, as they try to cut energy expenses. In the United States, “cool roofs” are standard equipment at Wal-Mart stores. More than 75% of the chain’s outlet stores have white roofs.

Most roofs, whether asphalt-shingle or tile, have a life span of 20 to 25 years. Rosenfeld says a “cool roof” doesn’t cost much more to install than a dark one, depending on the materials used. So, if you’re due for a new roof, or if you’d simply like to make an investment that’ll pay off down the road, consider “going cool.” You can find out more at CoolRoofs.org.