A construction worker carries a piece of foam insulation as he builds the frame of a house at a new housing development
There's a sexy side to green technology. Have you heard of solar panels that use nanotechnology? Algae that can be raised to make carbon-neutral biofuel? How about devices that generate power from the motion of the ocean, or even backpack wind turbines — O.K., maybe not.
But for all the interest in Silicon Valley science fiction, the most cost-effective green technology can be found in our own homes, simply by improving the energy efficiency of our houses and apartments. On average, heating an American home with natural gas creates about 6,400 lbs. of CO2 a year; using electricity will produce about 4,700 lbs of emissions. Both numbers can be larger if you live in a cold part of the country. The problem is that many American houses are poorly constructed and insulated, leaking heat in winter and cool air in the summer — and that's not cheap. Oil and gas prices may have declined in recent months — of course, fuel costs in the U.S. have also been historically low, compared to our counterparts in much of Europe — but most experts believe that's only temporary and expect to see significantly higher costs to heat and cool our homes in the future. For poor families, especially those on fixed incomes, a drafty house can eat up a large chunk of their income in the winter. The leakier the home, the more money you're wasting — and the more carbon you're spewing. (See TIME's special report on the environment.)
"Think of your house as a boat," says Richard Trethewey, the mechanical systems expert for PBS' home-improvement series This Old House. "If all the holes in your house that are letting out air were letting water in, it would sink your boat." (Listen to Trethewey talk about how to improve the energy efficiency of your home on this week's Greencast.)
Trethewey's advice is simple: Plug up those holes. "If you see light coming through from outside, that means heat is leaving the building," he says. Windows can be particularly tricky: It's easy to forget to lock your windows (unless you live in my New York City neighborhood), but unlocked windows, even when shut, can bleed heat on a cold day. "You might walk by that window outside and think it's nothing, but if you took that thin crack and turned it into a circle, you'd have a hole as big as a nickel or dime," says Threthewey. You can feel for leaks in walls — especially at corners or where different materials meet — and fill the gaps with caulk.
Trethewey also suggests investing in a home energy audit to help figure out exactly where the holes are. Such audits aren't cheap — they can range up to $800 — but as "fuel costs rise, the payback improves," notes Trethewey. A good auditor will use a blower test, which lowers the air pressure inside a home — air from the outside will then rush through openings, revealing any leaks. A truly high-tech test will use thermographic cameras, which detect infrared light, to detect exactly where heat might be leaking.
Another quick fix is to simply to use less heat — without freezing to death. Trethewey notes that many homes are overheated, equipped with boilers or heating systems that are far stronger than necessary. If a building uses about 100,000 BTU of heat, it doesn't need a system that supplies twice that — yet that's how many buildings operate. "It would be correct for about two percent of the year, and overpower you for the rest," says Trethewey. "It's like a V12 engine in a Volkswagen — it leads to wasted energy."
These fixes may not be free, but the good news is that there are federal tax credits — you can earn up to $500 for improving your insulation, and up to $200 for putting in more energy-efficient windows. But if America is going to get serious about weatherproofing the country and saving all the energy leaking out of its homes, the country needs stronger policies that will make going green the smart choice economically, not just environmentally. "We don't have it," says Trethewey. Low energy costs "have made us all pretty lazy and stupid." Winter's coming, though — even as the world gets warmer — and we need to get smarter, fast.