I'm not sure ethanol is the answer. I don't see a way of processing it without requisite CO2 byproduct. There WILL be a successor to petroleum and the sooner we get to it, the better. It should be another 10 year challenge like the moon program.
"We choose to go to alternative fuels. We choose to do this in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.