Before every new technology there comes the moment of invention. Before there was ethanol, someone had to look at biomass and say, "There's energy in them thar leaves." For the last day of our Power Trip energy series, venture capitalist Vinod Khosla joins The Takeaway from the TED conference in Long Beach, California. Khosla, whose company risks millions of dollars every year to fund upstart energy technologies, ruminates on creating billion dollar industries out of wild ideas.

Bill Gates, Microsoft founder and philanthropist, addressed the crowd at this year's TED conference with his thoughts on saving the world with a new kind of philanthropy. It's long, but funny. Really.

Just how power hungry is internet giant Google? The Takeaway's Power Trip heads to the Google campuses in Mountain View, California to find out. John Hockenberry sits down with Bill Weihl, the company's green energy czar (that's his title, no joke). On the interview agenda: the company's top picks for which alt-energy sources will rule the future clean energy economy, including solar with a twist. Plus, Weihl talks about the need for government energy subsidies, and why the company still ain't talking about the power consumed by a Google search

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If you knew where all the energy zooming into your house was being used and wasted, would you change the way you consume power? One company is banking on it. Our Power Trip heads to Redwood City, California to talk to Joe Polastre, CTO and co-founder of Sentilla. The company has invented an unassuming rectangular box that tracks —dollar by dollar, watt by watt—how much energy the appliances in your home are using. Clothes dryers and air conditioners beware: your energy guzzling ways are secrets no more.

Civics class may teach you that voters weigh the issues and choose the candidate who matches their positions, but several studies suggest that voters are not rational. They are rationalizers.

This summer, British and Canadian researchers plan to test new technology for releasing previously unrecoverable energy trapped in heavy oil deposits. It works by stimulating tiny microbes to chew up the sticky, tar-like heavy oil and metabolize it into natural gas.