Published on October 22nd, 2007 | by Stephanie Evans

Biodiesel Fuel

Biodiesel fuel is a replacement for standard diesel fuel. This alternative fuel is used only in diesel engines and as a substitute for standard gasoline or standard combustion engines. Biodiesel is a product of the transesterification of vegetable or nut oils into a fuel to be used in automobiles and even home heating.

So what is transesterification? Simply stated, it is the process of neutralizing the free fatty acids and removing the glycerin of the oil used as a base for the fuel to create an alcohol ester. This process is important for two reasons:

First, this process separates biodiesel fuel from using straight vegetable oil or waste vegetable oil as a fuel. Diesel engines have the ability to run on vegetable oil. In fact, the original engine created by Rudolph Diesel ran on peanut oil. At the time, it was found that petroleum based diesel fuel was cheaper so it was modified to run using a fossil fuel rather than a renewable one.

The second reason that transesterification is important relates to modifying the diesel engine. In order for an automobile to utilize vegetable oil as a fuel source, the engine needs to be modified to handle this. The use of biodiesel fuel does not require any such modification. Manufacturers do recommend changing the fuel filter frequently since biodiesel cleans the engine to the point that residue left over from standard diesel fuel is scrubbed loose and can clog the filter very quickly.

Oils used to make biodiesel fuel are found in corn, coffee, rice, nuts, and algae. One acre of corn is able to produce 18 gallons of biodiesel fuel. On the high end, it is estimated that algae can produce anywhere from 5,000 to 20,000 gallons of fuel per acre. The next closest source to algae’s production is the Chinese Tallow, which can produce about 699 gallons of fuel per acre.