I was thinking about the above when I saw this:

Another Blow to Ethanol: Biolectricity is Greener. By Bryan Walsh, Time, May 10, 2009. "Once touted as an environmental and economic cure-all, corn ethanol has had a rough year. The collapse in grain and oil prices, preceded by overinvestment in refineries over the past few years, badly hurt ethanol producers. Meanwhile, environmentalists have steadily chipped away at ethanol's green credentials. Far from being better for the planet than gasoline, many scientists now argue that ethanol actually has a sizable carbon footprint, because when farmers in the U.S. use their land to grow corn for fuel rather than food, farmers in the developing world end up cutting down more forests to pick up the slack. Now a new study makes the case that ethanol isn't even the greenest way to use biomass as a fuel. In an article published in the May 8 issue of Science, researchers from the Carnegie Institution, Stanford University and the University of California-Merced (UCM) used life-cycle analysis -- which takes into account the entire impact of a biofuel from field to vehicle -- to show that converting biomass to electricity (to power electric cars) produces 80% more transportation energy than turning it into ethanol (to power a flex-fuel car), with a carbon footprint that is half as small."