Biodiesel is a diesel fuel substitute that can be made from a variety of oils, fats, and greases. Biodiesel is not the same as straight vegetable oil or animal fat. A normal diesel engine will eventually be damaged through the use of straight vegetable oil or animal fat. Vegetable oils or animal fats must be converted into biodiesel by reacting the oil or fat with an alcohol and a catalyst.
Biodiesel is also not the same as bioethanol. Bioethanol is an alcohol made from fermented sugar, and is designed to be used in engines that run on gasoline. Biodiesel, on the other hand, is better suited for use in engines that normally use diesel fuel.
For more information, see Introduction to Biodiesel.
Contributor: Vern Grubinger, University of Vermont
