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http://discovermagazine.com/2010/dec/08-is-coal-killer-flying-thousands-feet-in-skyIn concept his idea makes sense: Wind power from the sky would strip turbines of their expensive, heavy towers and oversize blades, allowing them to collect energy unobtrusively from the richest lode of wind in the world. Winds at an altitude of 30,000 feet carry 20 times as much energy as those near the ground, representing a source of power that could be a fraction of the cost of coal. The challenge, observers say, is keeping such turbines aloft.
“Finding a resource so large is like finding an oil field in your garden,” says Cristina Archer, an environmental engineer at the University of California, Chico, and lead author of a global survey on high-altitude winds. “Plus, you’re saving on material costs by using 100-pound devices floating on air rather than 200 tons of cement for a traditional wind turbine.”