Biodiesel Fuel

Generally speaking, biodiesel is an alternative or additive to standard diesel fuel that is made from biological ingredients instead of petroleum (or crude oil). Biodiesel is usually made from plant oils or animal fat through a series of chemical reactions. It is both non-toxic and renewable. Because biodiesel essentially comes from plants and animals, the sources can be replenished through farming and recycling.

Although biodiesel can be used in its pure form, it is usually blended with standard diesel fuel. Blends are indicated by the abbreviation BXX, where XX is the percentage of biodiesel in the mixture. For example, the most common blend is B20, or 20 percent biodiesel to 80 percent standard. B100 refers to pure biodiesel. Biodiesel is safe and can be used in Ford F-550 diesel engines up to a B20 blend with no modification needed.

There is a formal, technical specification for biodiesel recognized by ASTM International – the organization responsible for providing industry standards. According to the National Biodiesel Board (NBB), the technical definition of biodiesel is:

a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, designated B100, and meeting the requirements of ASTM D 6751.

Part of what makes biodiesel so appealing and interesting is that it can be made from numerous natural sources. Although animal fat can be used, plant oil is the largest source of biodiesel. You’ve probably used some of these in the kitchen. Scientists and engineers can use oils from familiar crops such as soybean, rapeseed, canola, palm, cottonseed, sunflower and peanut to produce biodiesel. Biodiesel can be made from recycled cooking grease – and even algae! The common thread shared by all biodiesel sources is that they all contain fat in some form. Oils are just fats that are liquid at room temperature.

The concept of biofuels is surprisingly old. Rudolf Diesel (whose invention now bears his name) had envisioned vegetable oil as a fuel source for his engine. In fact, much of his early work revolved around the use of biofuel. In 1900, for example, at the World Exhibition in Paris, Diesel demonstrated his engine by running it on peanut oil. Similarly, Henry Ford expected his Model T to run on ethanol, a corn product. Eventually, in both Diesel’s and Ford’s cases, petroleum entered the picture and proved to be the most logical fuel source. This was based on supply, price and efficiency, among other things. Though it wasn’t common practice, vegetable oils were also used for diesel fuel during the 1930s and 1940s.

Biodiesel has several key advantages:

  • Biodiesel is environmentally friendly.
  • Biodiesel can help reduce dependency on foreign oil.
  • Biodiesel helps to lubricate the engine itself, decreasing engine wear.
  • Biodiesel can be used in most diesel engines with little or no modification.
  • Biodiesel is safer than conventional diesel.

One of the major selling points of biodiesel is that it is environmentally friendly. Biodiesel has fewer emissions than standard diesel, is biodegradable, and is a renewable source of energy.

Emissions control is central to the biodiesel argument, especially in legislation matters – but this argument carries less weight with new clean diesel engines. There are a few components of emissions that are especially harmful and cause concern among scientists, lawmakers, and consumers. Sulfur and its related compounds contribute to the formation of acid rain; carbon monoxide is a widely recognized toxin; and carbon dioxide contributes to the greenhouse effect.

Biodiesel reduces hazardous emissions. Of the current biofuels, biodiesel is the only one to have successfully completed emissions testing in accordance with the Clean Air Act.

Average Biodiesel Emissions Compared to Conventional Diesel

Emission   Component


Total Unburned   Hydrocarbons


Carbon Monoxide


Particulate   Matter








Source:   National Biodiesel Board


Another feature of biodiesel is that it is biodegradable, meaning that it can decompose as the result of natural agents such as bacteria. According to the EPA, biodiesel degrades at a rate four times faster than conventional diesel fuel. This way, in the event of a spill, the cleanup would be easier and the aftermath would not be as frightening. This would also hold true for biodiesel blends.

Biodiesel use lowers U.S. dependence on imported oil and increases our energy security. Most biodiesel in the U.S. is made from soybean oil, which is a major domestic crop. With U.S. petroleum demands increasing and world supply decreasing, a renewable fuel such as biodiesel, if properly implemented, could alleviate some of the U.S. energy demands.

Biodiesel also contributes to an engine’s lubricity, or its ease of movement. Biodiesel acts as a solvent, which helps to loosen deposits and other gunk from the insides of an engine that could potentially cause clogs. Since pure biodiesel leaves no deposits of its own, this results in increased engine life. It is estimated that a biodiesel blend of just 1 percent could increase fuel lubricity by as much as 65 percent (U.S. DOE Office of Transportation Technology).

Biodiesel is also safer. It is non-toxic (about 10 times less toxic than table salt) and has a higher flashpoint than conventional diesel. Because it burns at a higher temperature, it is less likely to accidentally combust. This makes movement and storage regulations easier to accommodate.

Where can I buy biodiesel?


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