The challenge of helping the world consume fuel more efficiently is a highly complex business that owes a lot to cutting edge science and technology. But when U.S. Energy Secretary Steven Chu appeared on Comedy Central recently, he offered some decidedly low-tech advice: Make it White.
White, as in white roof, that is. Chu reminded his modern audience of a basic fact that dwellers of warm climates have understood for centuries: when you paint a roof, or even an entire house white, it absorbs less heat. Way back when, that simply meant that everyone was a little bit more comfortable. Today, it means less air conditioning, lower electricity bills and reduced emissions. By Chu’s own account, if the world could somehow manage to turn all its roofs white within 20 years, it would save about 24 billion metric tons of carbon dioxide emissions – the same amount the entire world emitted last year. “So, in a sense, it’s like turning off the world for a year.” It’s a rhetorical argument of course, but it does show that little changes can add up.
The New York Times cites studies showing that in hot, sunny climates, white roofs reduce air-conditioning costs by at least 20%. They are not much more expensive than standard darker roofs and the investment can pay for itself quickly.
One disclaimer: People who live in places that have cold winters should probably keep dark roofs, which during cold, sunny days help keep homes warmer and reduce heating costs. But if you hail from a place like Arizona or Florida or southern California, take Chu’s advice and go light. Saving energy doesn’t always have to be so complicated.