What You Need to Know About Using Biodiesel in Your Fleet Trucks

Biodiesel, n—a fuel composed of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats.

Petroleum-based fuel is available in a finite amount, so the time to be looking at alternative fuel sources is now. Biodiesel is one such alternative and it is a clean burning alternative fuel and in 2010, 315 million gallons were produced, according to the National Biodiesel Board. Biodiesel contains no petroleum, but it can be blended at any level with petroleum diesel to create a biodiesel blend, and it can be used in diesel engines with no major modifications. Biodiesel is simple to use, biodegradable, nontoxic, and essentially free of sulfur and aromas.

Biodiesel is registered as a fuel and fuel additive with the Environmental Protection Agency (EPA) and meets clean diesel standards established by the California Air Resources Board (CARB). Pure, or 100 percent, biodiesel has been designated as an alternative fuel by the Department of Energy (DOE) and the US Department of Transportation (DOT), according to the National Biodiesel Board.

Biodiesel can be used in pure form or blended with petroleum in any percentage. B20, a blend of 20 percent by volume biodiesel with 80 percent by volume petroleum diesel, has shown major environmental benefits with little increase in cost for fleet operations and other consumers. UPS has even taken to using biodiesel in their trucks at their Louisville, Kentucky headquarters.

A 1998 biodiesel lifecycle study, jointly sponsored by the US Department of Energy and the US Department of Agriculture, concluded biodiesel reduces net CO² emissions by 78 percent compared to petroleum diesel. This is due to biodiesel’s closed carbon cycle. The CO² released into the atmosphere when biodiesel is burned is recycled by growing plants, which are later processed into fuel.

And scientific research confirms that biodiesel exhaust has a less harmful impact on human health than petroleum diesel fuel. Biodiesel emissions have decreased levels of polycyclic aromatic hydrocarbons (PAH) and nitrited PAH compounds that have been identified as potential cancer causing compounds. Test results indicate PAH compounds were reduced by 75 to 85 percent, with the exception of benzo(a)anthracene, which was reduced by roughly 50 percent. Targeted nPAH compounds were also reduced dramatically with biodiesel fuel, with 2-nitrofluorene and 1-nitropyrene reduced by 90 percent, and the rest of the nPAH compounds reduced to only trace levels.

In general, the standard storage and handling procedures used for petroleum diesel can be used for biodiesel. The fuel should be stored in a clean, dry, dark environment. Acceptable storage tank materials include aluminum, steel, fluorinated polyethylene, fluorinated polypropylene and teflon. Copper, brass, lead, tin, and zinc should be avoided.

If biodiesel comes in contact with brass, bronze, copper, lead, tin, and zinc for a prolonged period of time, B20 will degrade and create sediments. Lead solders and zinc linings should be avoided, as should copper pipes, brass regulators, and copper fittings. Affected equipment should be replaced with steel or aluminum. The effect of B20 on vulnerable materials is significantly reduced compared to higher blends.

In addition, biodiesel in its purest form can soften and degrade certain types of gasket, hose, and seal compounds like natural rubber, Buna-N, and nitrile, which can create fuel system leaks. This affect has NOT been observed with blends of B20 and lower over the last 10 years of B20 experience, so B20 or lower blends can be used without changes. If it is desired to use blends over B20, the engine or vehicle manufacturer should be contacted to determine if the seals, hoses, and gaskets are compatible with the blend being considered before use.

When reviewing the high costs associated with other alternative fuel systems, many fleet managers have determined biodiesel is their least-cost-strategy to comply with state and federal regulations. Use of biodiesel does not require major engine modifications, which means that operators keep their fleets, their spare parts inventories, their refueling stations and their skilled mechanics. The only thing that changes is air quality.

Biodiesel is the only alternative fuel to have fully completed the health effects testing requirements of the Clean Air Act. The use of biodiesel in a conventional diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and particulate matter compared to emissions from diesel fuel. In addition, the exhaust emissions of sulfur oxides and sulfates from biodiesel are essentially eliminated compared to diesel.

The use of biodiesel results in a substantial reduction of unburned hydrocarbons, one of the leading exhaust pollutants and contributors to smog and ozone depletion. The emissions of the other major exhaust pollutant, nitrogen oxide, are either slightly reduced or slightly increased depending on the duty cycle of the engine and testing methods used. Based on engine testing, using the most stringent emissions testing protocols required by EPA for certification of fuels or fuel additives in the US, the overall ozone forming potential of the speciated hydrocarbon emissions from biodiesel was nearly 50 percent less than that measured for diesel fuel.

Scientific research confirms that biodiesel exhaust has a less harmful impact on human health than petroleum diesel fuel. Biodiesel emissions have decreased levels of polycyclic aromatic hydrocarbons (PAH) and nitrited PAH compounds that have been identified as potential cancer causing compounds. Test results indicate PAH compounds in B20 were reduced by 13 percent.

Biodiesel is available anywhere in the United States and can be used in any climate. It has been used during the winter in Minnesota and Montana without any cold flow issues, which in the B20 blend, are mainly determined by the petroleum fraction. The National Biodiesel Board is an amazing resource for finding information, facts, as well as registered fuel suppliers. Visit www.biodiesel.org or call (800) 841-5849 for more information.