11 great green ideas

Imagine a fuel that can burn in today's cars, trucks, and jets while reducing greenhouse-gas emissions by as much as 80%. A pipe dream? Not according to the founders of Amyris, a five-year-old company in Emeryville, Calif. Scientists Jay Keasling and Jack Newman have designed a microorganism that acts like a tiny factory, constantly fermenting sugar and excreting a hydrocarbon with properties similar to gasoline, diesel, and kerosene jet fuel. Amyris is putting its first bugs to work on sugarcane because growing and processing it releases fewer emissions than corn ethanol.
-- Brian Dumaine

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