Big ideas on carbon emissions swirl through a radical energy conference

I'm still humming from November's "Carbon Economy" summit in Washington. My highlight: Ten entrepreneurs showcasing their ideas on how to address renewable-energy demand, carbon mitigation, and green jobs. They presented their ideas to potential investors and energy executives, who voted for the smartest, savviest, likeliest game-changer.

And it was a tough contest. There was the bio-algae producer from Puerto Rico, and the wind turbines designed to float at sea. There was the company using national weather-service data to help India's farmers accurately predict rainfall -- and use less diesel energy for their generators. The ideas were so good, I couldn't narrow them down to one favorite. Here, instead, I present my own awards for the most surprising green ideas to come from the conference (one of which was the actual "winner").