Biodiesel Production and Distribution
Biodiesel is a legally registered fuel and fuel additive with the U.S. Environmental Protection Agency (EPA). EPA registration includes all biodiesel that meets ASTM D6751. EPA registration does not depend on oil or fat used to produce the biodiesel or the specific production process employed. The federal Renewable Fuel Standard requires at least 1 billion gallons of biodiesel consumption in the U.S. (referred to as biomass-based diesel).
Biodiesel is produced from vegetable oils, yellow grease, and tallow. The production process converts oils and fats into chemicals called long-chain mono alkyl esters, or biodiesel. These chemicals are also referred to as fatty acid methyl esters, and the process is referred to as transesterification. Roughly speaking, 100 pounds of oil or fat are reacted with 10 pounds of a short-chain alcohol (usually methanol) in the presence of a catalyst (usually sodium hydroxide [NaOH] or potassium hydroxide [KOH]) to form 100 pounds of biodiesel and 10 pounds of glycerin. Glycerin, which is used in pharmaceuticals and cosmetics, among other markets, is produced as a co-product. Although the process is relatively simple, homemade biodiesel is not recommended. Diesel engines are expensive, and it's not worth voiding the warranty or risking damage or minor operational problems from fuel that does not meet rigorous ASTM D6751 specifications.
Raw or refined plant oil, or recycled greases that have not been processed into biodiesel, are not biodiesel and should be avoided. Fats and oils (triglycerides) are much more viscous than biodiesel, and low-level vegetable oil blends can cause long-term engine deposits, ring sticking, lube-oil gelling, and other maintenance problems that can reduce engine life.
Research is currently focused on developing algae as a potential biodiesel feedstock, because it's expected to produce high yields from a smaller area of land than vegetable oils.
Biodiesel is distributed from the point of production to retail fueling stations by truck, train, or barge. Most biodiesel distributors will deliver B20 or B100 depending on the customer's preference. Find biodiesel distributors. For more information, see the National Biodiesel Board's Guide to Buying Biodiesel.