The Car and Truck Fleet and Leasing Management Magazine

Biodiesel by the Numbers

Biodiesel offers a straightforward path to a greener fleet. Before implementing, choose the right blend, know all fueling options, and understand engine warranty and maintenance obligations.

October 2010, by - Also by this author

Biodiesel, a form of diesel fuel produced from vegetable oils or animal fats, is the only alternative fuel that runs in any conventional diesel engine. As such, biodiesel offers a straightforward path to a greener fleet.  

Manufactured domestically, biodiesel cuts emissions of carbon monoxide, sulfur, smog-producing particulate matter, and carbon dioxide - the main greenhouse gas causing global warming.

Through rigorous standards, testing, and evaluation, biodiesel shed its early misperception as a vegetable oil "homebrew." Still, there are challenges to implementation, including limited retail availability, fluctuating pump prices, maintenance and performance concerns, and vehicle warranty issues. Here's a "how-to guide" to determine if biodiesel will work in your fleet.

Know the Standards

Biodiesel is blended with petroleum diesel for most retail fuel applications. Common blends are B-2 (2-percent biodiesel), B-5, B-20, and B-100 (pure biodiesel). B-20 is the most commonly used biodiesel blend in the United States. This blend provides a good balance between material compatibility, cold weather operability, performance, emission benefits, and costs, according to the National Renewable Energy Laboratory (NREL).

Standards development body ASTM International sets minimum accepted values for fuel properties. The standard for petroleum diesel fuel is ASTM D975, while ASTM D6751 covers pure biodiesel (B-100) for blending with petrodiesel in levels up to 20 percent by volume.

Today, biodiesel must meet the ASTM D6751 standard to be legally defined and sold at retail fueling stations. Further, producers and marketers of biodiesel have created a voluntary accreditation program of biodiesel fuel. BQ-9000 is a quality systems program for biodiesel storage, sampling, testing, blending, shipping, distribution, and fuel management.

Though these quality checks and balances are the industry rule, it is a good idea to confirm through documentation that your supplier adheres to accepted standards and accreditation, said Steven Levy, managing director of Sprague Energy, a supplier of traditional and alternative fuels.

Though quality checks and balances are the industry rule, Steven Levy of Sprague Energy recommends confirming through documentation that your supplier adheres to ASTM standards and BQ-9000 accreditation.

Check Engine Warranty

Check your vehicle engine manufacturers' warranty statements on biodiesel. Note that parts failures resulting from the use of any fuel are not covered.

Currently, most engine manufacturers state the use of up to B-5 blends will not void warranties, provided the fuel meets ASTM standards.
Chrysler, Cummins, Ford, General Motors, and International/Navistar have certified certain models for B-20. Other enginemakers are "currently completing research for B-20 support," according to the National Biodiesel Board (NBB) Web site,, which lists warranty statements for most manufacturers.

Fleets regularly use higher blends not covered in OEM warranty statements. While this runs the risk of voiding a warranty, fleet managers concentrate on the quality of the biodiesel to safeguard against parts failures.

Jim Evanoff, environmental protection specialist for Yellowstone National Park, said his supplier conducts his own tests in addition to ASTM certification. "We don't give it a thought, to be honest," Evanoff said. "We've never had a warranty issue." The park has been using varying blends of biodiesel for 15 years.

The New York City Department of Sanitation has been running B-5 for five years in close to 6,000 vehicles and started a B-20 pilot test in November 2009. Rocco DiRico, deputy commissioner for the Bureau of Support Services, reported no issues with engine malfunctions related to biodiesel.
Twitter Facebook Google+


Please note that comments may be moderated. 
Leave this field empty:

Fleet Incentives

Determine the actual cost of owning and running a vehicle in your fleet. Compare vehicles by class and model.


Fleet Tracking And Telematics

Todd Ewing from Fleetmatics will answer your questions and challenges

View All


Fleet Management And Leasing

Jack Firriolo from Merchants will answer your questions and challenges

View All


Fuel Management

Bernie Kanavagh from WEX will answer your questions and challenges

View All


Sponsored by

Armund Schoen was the cofounder of Wheels Inc. and Zollie Frank's brother-in-law.

Read more

Fuel Saving Strategies Survey

View our 2008 survey to benchmark your fleet's fuel and green strategies with other fleets.

Fuel Calculator

A managed fuel program can help you save time and money and gain control over the way you fuel your vehicles. Determine your potential savings by using our fuel calculator.
Launch Fuel Calculator 

Fuel Prices

U.S. Gasoline and Diesel Fuel Prices.

Launch Fuel Prices 

Up Next

More From The World's Largest Fleet Publisher