And it's bad for the environment

OK, so we already know what a bad deal corn-based ethanol is from an energy standpoint — that is, the amount of energy it requires to produce a gallon of ethanol is roughly the same as you get from the gallon of ethanol itself.

Now we learn it's also a bad deal from a greenhouse gas standpoint:

Biofuels, once championed as the great hope for fighting climate change, could end up being more damaging to the environment than oil or gasoline. A new study has found that the growth and use of crops to make biofuels produces more damaging greenhouse gases than previously thought.

German Nobel-prize winning chemist Paul Crutzen and his team of researchers have calculated the emissions released by the growth and burning of crops such as maize, rapeseed and cane sugar to produce biofuels. The team of American, British and German scientists has found that the process releases twice as much nitrous oxide (N2O) as previously thought. They estimate that 3 to 5 percent of nitrogen in fertilizer is converted and emitted, as opposed to the 2 percent used by the Intergovernmental Panel on Climate Change in its calculations.

Crutzen is widely respected in the field of climate research, having received the Nobel Prize in 1995 for his research into the ozone layer. The study, published in the scientific journal Atmospheric Chemistry and Physics, finds that the growth and use of biofuels produced from rapeseed and maize can produce 70 percent and 50 percent more greenhouse gases respectively than fossil fuels.

So there's something else to remember next time you see one of those feel-good commercials from Archer Daniels Midland.  And here are some more facts to load up your ethanol arsenal.