Biodiesel is a renewable fuel for diesel engines derived from natural oils and fats (vegetable oils, recycled cooking greases or oils, and animal fats) that specifically meets the specifications of ASTM D 6751. Biodiesel is composed of monoalkyl esters of long-chain fatty acids, produced by the transesterification with alcohol from natural oils and fats. As a DOE-designated alternative fuel, biodiesel is registered as a fuel and fuel additive with the U.S. Environmental Protection Agency (EPA).
Biodiesel is non-toxic and biodegradable, and offers many benefits over conventional petroleum diesel fuel:
- Biodiesel burns cleaner (than petroleum diesel fuel), with net emissions reductions in particulates, hydrocarbons, and carbon monoxide (and with zero-to-slight increases in NOx.
- With biodiesel’s high energy balance of 3.2 to 1, it provides a beneficial 78 percent life-cycle CO2 reduction .
- Biodiesel possesses a high cetane number (averaging over 50) and improves petroleum diesel cetane performance when blended.
- Biodiesel is naturally low in sulfur content and lowers sulfur emissions when blended with petroleum diesel.
- Biodiesel blending imparts improved lubricity to petroleum diesel.
A critical additional advantage: because biodiesel is domestically produced, it shows great potential for reducing U.S. dependence on foreign energy supplies. Biodiesel provides a “closed economic loop” because the feedstock can be grown locally, biodiesel can be produced locally, and the fuel can be used locally. Furthermore, it is evident that very-minimal-to-no infrastructure change is required to implement widespread biodiesel use. Biodiesel blends can be used in any diesel engine and can be transported and stored using existing infrastructure. While there has been an exponential growth in biodiesel production in the U.S. in the last few years , biodiesel currently represents less than 1 percent of total diesel fuel used in the U.S., making the diesel market wide open for quality bio-based diesel fuel.