Like most too good to be true stories, "green fuels" are a starting point, not a silver bullet.
http://en.wikipedia.org/wiki/Ethanol_fuel#Net_fuel_energy_balance
Net fuel energy balance
For ethanol to contribute significantly to transportation fuel needs, it would need to have a positive net energy balance. To evaluate the net energy of ethanol four variables must be considered: the amount of energy contained in the final ethanol product, the amount of energy directly consumed to make the ethanol (such as the diesel used in tractors), the quality of the resulting ethanol compared to the quality of refined gasoline and the energy indirectly consumed (in order to make the ethanol processing plant, etc). Although a topic of debate, some research that ignores energy quality suggests it takes as much or more fossil fuel energy (in the forms of diesel, natural gas and coal) to create an equivalent amount of energy in the form of ethanol. In other words, the energy needed to run the tractors, produce the fertilizer, process the ethanol, and the energy associated with the wear and tear on all of the equipment used in the process (known as fixed asset depreciation to economists) may be more than the energy derived from burning ethanol.
Please tell me you didn't just use a wikipedia as a source.