Ethanol according to Collin Dunn at TreeHugger.com is "also known as ethyl alcohol, the same kind of alcohol you shake with vermouth and serve with some olives. Used as a fuel, it is often added to gasoline (notated much the same as biodiesel: E10 means 10% ethanol; E85 means 85% ethanol, and so on)."

Ethanol "can be produced from any biological feedstocks that contain appreciable amounts of sugar or materials that can be converted into sugar such as starch or cellulose. Sugar beets and sugar cane are examples of feedstocks that contain sugar. Corn contains starch that can relatively easily be converted into sugar. A significant percentage of trees and grasses are made up of cellulose, which can also be converted to sugar, although with more difficulty than required to convert starch."

"Compared with conventional unleaded gasoline," Dunn explains, "ethanol is a particulate-free burning fuel source that combusts cleanly with oxygen to form carbon dioxide and water. Use of ethanol, produced from current methods, emits a similar net amount of carbon dioxide but less carbon monoxide than gasoline."

There are two major criticisms of ethanol. "Many say that it is just as bad as gasoline, because cars get poor gas mileage when they are fueled by ethanol, writes Josh Peterson at Planet Green. But Peterson cites a UC Berkeley study that found that using ethanol reduces greenhouse emissions by ten to fifteen percent.

The other major criticism of ethanol is that it wastes food. "This is not completely true," says Peterson. "Corn is used to create ethanol, and corn is a type of food. Ethanol production, however, does not utilize the entire kernel. The process mainly involves the starches. Ethanol production leaves most of the protein behind. That leftover corn can be fed to livestock. Fifty percent of all corn is fed to livestock anyways."

And therein lies the larger problem.