Here's an excerpt from the article.
The Ethanol Boondoggle A study last year by Cornell University scientist David Pimentel highlighted
another problem. Most replacements for gas--including ethanol--have to be
manufactured. It turns out this process is both energy-intensive and expensive. Pimentel's analysis showed that it takes about 70 percent more energy to produce ethanol than the resultant ethanol yields. The additional energy comes from, you guessed it, fossil fuels.
Pimentel found it costs $1.74 to produce a gallon of ethanol, twice that for
gasoline. He notes that's why "fossil fuels--not ethanol--are used to produce ethanol.... Growers and processors can't afford to burn ethanol to make ethanol."
So whacha burning in them big ol tractors.......................