While he was working in Haiti, inventor Shawn Frayne, one of the recipients of Popular Mechanics' 2007 Breakthrough Awards last week, recognized the need for small-scale wind power to power LED lamps and radios in impoverished homes. But conventional wind turbines don't scale down well, because of too much friction in the gearbox and other components.
Inspired by aeroelastic flutter, the same phenomenon that brought the Tacoma Narrows Bridge crashing down in 1940, Frayne came up with an elegantly simple solution: The Windbelt, a taut membrane fitted with two magnets that oscillate between metal coils. Prototypes have generated 40 milliwatts in 10-mph gusts of wind, making Frayne's device about 10 to 30 times more efficient than the best microturbines. And because the Windbelt will only cost a few dollars to make and is easily repairable by locals, it's also a technology that is appropriate to the environmental, cultural, and economic circumstances under which it'll be used—a key consideration many designers and engineers are now clueing into.