QUOTE (Rex Kicka** @ Oct 19, 2009 -> 02:42 PM)
Sugarcane says hi.
Half the emissions of regular gas. Rapidly renewable, its what led Brazil to energy independence.
No, finding oil supplies offshore did that. They've made a dent with sugarcane, but the U.S. isn't exactly the climate for that. The U.S. actually consumes more ethanol than Brazil does as well, because Brazil consumes so much less energy. According to the EIA in 2006, ethanol made up ~50% of the fuel for Brazil's passenger vehicles, but only 20% of it's total fuel consumption (Diesel trucks, etc.)
Sugarcane is a niche thing in terms of ethanol production. If you have the right climate it can work. But if you have to cut down, let's say, a gigantic rainforest to clear space to grow the sugarcane, you lose all of the possible benefits of replacing oil with ethanol in terms of carbon emissions and pollution. And you lose some irreplaceable rainforest too.