This third article by Absolute Futures will show how many bushels of corn are needed to make just one gallon of ethanol. This will show anyone who trades in corn how the production of ethanol affects the total amount of corn that can be used to feed livestock and for other domestic uses.
Up to 2.5 gallons of ethanol fuel can be made from a bushel of corn. To make ethanol, only the starch from the corn is used. Most of the corn kernel is still there, so the protein and other valuable byproducts can be used to make food for people, feed for animals, and different chemicals. For example, the same bushel of corn (56 lbs.) used to make ethanol can also be used to make the following things, depending on how ethanol is made. Ethanol can be made from corn by using either the wet-milling or dry-milling process. Dry-milling plants cost less to build and make more ethanol, but the co-products they make are worth less.
Wet milling makes 31.5 pounds of starch, 33 pounds of sweetener, 2.5 gallons of ethanol fuel, 12.4 pounds of feed with 21% protein, 3.0 pounds of feed with 60% gluten, 1.5 pounds of corn oil, and 17 pounds of carbon dioxide.
The process of dry milling 2.5 gallons of ethanol fuel and 15 pounds of brewer's yeast, 10 eight-ounce packages of cheese curls, 1 pound of pancake mix, 22 pounds of hominy feed for live cattle, 0.7 pounds of corn oil, and 17 pounds of carbon dioxide.
The amount of "net energy" used to make ethanol is one of the most controversial things about it. Research done in 1995 by the Institute for Local Self-Reliance found that making ethanol from corn creates more energy than it uses. If corn farmers use energy-efficient, state-of-the-art farming methods and ethanol plants use energy-efficient, state-of-the-art production methods, then a gallon of ethanol and the other byproducts contain more than twice as much energy as was used to grow the corn and turn it into ethanol.
