Biodiesel
Biodiesel is one of the major biofuels available these days - that is, fuels made from biological ingredients rather than fossil fuels such as petroleum (or crude oil). The technical definition according to the National Biodiesel Board (NBB) 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.
The European standard for biodiesel is EN 14214 (BS EN 14214 in Britain, DIN EN 14214 in Germany etc). Biodiesel can be used on its own in most diesel engines or it can be blended with petro-diesel, for which a B factor is often used to state the fuel mix ratio. For example:
| Name | Mix |
|---|---|
| B100 | 100% biodiesel |
| B50 | 50% biodiesel / 50% petrodiesel |
| B20 | 20% biodiesel / 80% petrodiesel |
| B5 | 5% biodiesel / 95% petrodiesel |
When deciding to switch to using biodiesel in a diesel engine, it is wise to start with a blend such as B20 for a few weeks before proceeding onto straight (B100) biodiesel. Also you may wish to change your fuel filter after a few weeks too - not because the biodiesel is dirty in any way, but because it will tend to clean your engine of older desposits that have built up over time. As a result, biodiesel can actually be good for your engine.
Advantages of Biodiesel
Biodiesel comes with many advantages over regular diesel (petro-diesel). It is a lubricant and so reduces engine wear, is non-toxic and virtually carbon neutral, produces fewer harmful emissions and is readily sustainable unlike fossil-based fuels, for which resources are gradually running out. It is also safer to use and transport, thanks to having a higher flash point. These advantages will be explained further later on in this guide.
Biodiesel History
The exact origins of biodiesel are a little unclear. Although the diesel engine gets its name from its inventor, Rudolf Diesel, who saw the merits of using biodiesel, biodiesel was most probably discovered a few years earlier by chemists making soap. Transesterification, turning vegetable oils into combustible fuel, was certainly carried out in 1853 by two chemists, E. Duffy and J. Patrick.