11 great green ideas

Makani Power aims to generate energy from what are known as high-altitude wind-extraction technologies. And that's about all its 34-year-old Aussie founder, Saul Griffith, wants to say about it right now. But Makani can't hide entirely, not when its marquee investor is Google.org, the tech company's philanthropic arm. Harnessing high-altitude wind, at least in theory, has greater potential than the existing wind industry, which generates about 1% of U.S. electricity needs; a thousand feet above ground, wind is stronger and more consistent. -- Adam Lashinsky

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