Home - Background: Fuel Types - B20 -
Biodiesel is to petroleum diesel fuel what ethanol (E85) is to gasoline: a substitute fuel made from biomass, which means that it is inherently renewable and, in itself, it contributes nothing to carbon-dioxide loading of the atmosphere. Biodiesel commonly uses soybean or canola oil as its base, but animal fat or recycled cooking oil can also be used. To speed its market introduction, and dilute its additional cost over petroleum diesel fuel, the initial commercial product being studied is a blend of 20% biodiesel and 80% petroleum diesel fuel, whence B20.
Biodiesel is not currently widely available, though production-scale plants (as opposed to laboratory-scale experimental setups) do exist, for example NOPEC.
See above; you can't buy biodiesel readily yet, though retail stations are starting to appear. However, B20 requires absolutely no change in the storage or dispensing hardware that handles petroleum diesel fuel, and even "neat" biodiesel (or "B100") would only require minor changes in some materials used for seals, hoses and the like. Thus the retail infrastructure for a B20 market is already in place. (It's also possible to burn straight vegetable oil (SVO) in a diesel engine, either "virgin" or used (french-fry grease!), but this requires an extra tank for the fuel and the engine has to start and warm up on regular diesel fuel. However, you may be able to get waste vegetable oil from a local restaurant for free!)
As noted above, B20 can be stored and dispensed in exactly the same manner as petroleum diesel fuel; in addition, diesel-powered vehicles require no modification at all to run on B20 or even higher blends. Thus any diesel-powered truck or bus is, potentially, already an alternative-fueled vehicle! For example, an ordinary used Winnebago was "converted" into the Veggie Van simply by pouring homemade biodiesel into its tank. Since biodiesel is not a fossil fuel, as noted above, it can cut greenhouse-gas emissions as well as ordinary pollutants (particularly soot) by displacing petroleum diesel fuel.
The main disadvantage of B20, like that of E85, is fuel cost. However, since it requires no changes in hardware (vehicle or refueling) or retraining of mechanics and users, studies have shown that it could be the most cost-effective way for some fleets to meet clean-air requirements (compressed natural gas cuts fuel and maintenance costs, but vehicles must be replaced or converted to use it, and mechanics must be retrained, which may tip the balance).
new 11 July 1998, revised 2 September 2003