Meet the Champions of Clean Tech

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Kleiner Perkins Caufield & Byers

Kleiner Perkins Caufield & Byers, is perhaps one of the oldest names in clean tech capital--investing in 88 clean-technology companies since 1999. But the firm, among those bitten by the fading prospects of Fisker Automotive, has been forced to reevaluate its investment strategy. In 2010, the group hired "Queen of the Net" and Morgan Stanley alumna Mary Meeker to steer its investment portfolio. Now, the firm's green portfolio companies have a more stereotypical tech slant. Among them: smart thermostat manufacturer Nest and OPower, a Web platform that offers energy-efficient solutions for utilities companies.