More info about the inefficiencies of ethanol here:
http://healthandenergy.com/ethanol.htm
http://www.sciencedaily.com/releases...0329132436.htm
The US government contests these analyses. An overview of the factors involved is here:
http://en.wikipedia.org/wiki/Ethanol...energy_balance
Improvements in the fermentation process which allow ethanol to be produced from cellulose, rather than food components like starch and sugar, may tip the balance. But for now, I think conservation and improved efficiency are a better short-term bet. There are an awful lot of hungry people in this world. I'm not keen on a system that turns food into energy.
Medium term, I'd like to think this might work:
http://www.mindfully.org/Energy/2003...-Oil1may03.htm
http://en.wikipedia.org/wiki/Thermal_depolymerization