DALLAS, TX – A two million-mile over-the-road field test of biodiesel-blended fuel has passed the 1.6 million mile mark and should be wrapped up by November of this year, with detailed data analysis on fuel performance available by spring 2009.

“What this test is designed to do is provide a roadmap for the successful use of B20,” said Dr. Don Heck, coordinator of biotechnology and biofuels program at Iowa Central Community College, as well as the director of the two million-mile haul field test. “We want to define the fuel economy expectations of B20, proper handling procedures, and its cold weather performance.”

B20 is a blended fuel made up of 20% biodiesel – in this case made largely from soybean oil – with 80% regular No. 2 diesel fuel. Refrigerated and flatbed carrier Decker Truck Lines of Ft. Dodge, Iowa, agreed in August 2006 to participate in the study with 20 trucks in its 600 truck fleet – 10 operating on diesel and 10 using B20 biodiesel.

To date, Heck noted that the fuel economy difference between B20 and regular diesel is around 2% for the entire study, narrowing to 1% in the summer months. On average, Decker’s Peterbilt 378s and 386s equipped with 475 hp Caterpillar engines are achieving 6.25 mpg with diesel and 6.12 mpg with B20. Those 20 trucks are all in flatbed operation, hauling full 80,000-lb. loads of construction materials on set, round-trip routes between Ft. Dodge to Chicago and Ft. Dodge to Minneapolis.

Steve Lursen, special projects manager at Decker, said the price of B20 has fluctuated significantly over the course of the study, changing the economic side of the fuel equation frequently. “At the beginning, B20 was eight to 12 cents cheaper than diesel,” he told FleetOwner. “Then it became 20 cents more expensive than diesel, Right now, it’s even with diesel. What we learned from this is that fleets need to look at the economics closely, adjusting their blend if they need to based on pricing changes.”

Heck noted that other B20 metrics are being confirmed by the study as well. So far, petroleum diesel has a higher energy content, with 2.7% more BTUs [British Thermal Units] than B20. But B20, in turn, has a 1.8-point higher cetane rating. Oil analysis so far shows that B20 produces more soot in the oil, while there’s been a higher level of some metals in the oil from using regular diesel.

Heck added that cold-flow problems affected both B20 and regular diesel equally, especially around minus 20 deg. Fahrenheit. Both were treated heavily to avoid cold-flow problems, minimizing fuel filter plugging. Yet B20 plugged up filters more than petroleum diesel, as expected. Interestingly, Heck found that fuel filter heaters had little impact on the cold-flow issues of B20.

Despite the higher cost and slightly lower fuel economy, Decker’s Lursen noted that using biodiesel helped the carrier strengthen its “green” image and bolster its membership in the Environmental Protection Agency’s SmartWay program – efforts that are helping the company win more business.

“We’re seeing a lot of bid packages come in now that require carriers to be SmartWay members and to have ongoing ‘green’ initiatives,” Lursen said. “So what started as good corporate citizenship is now having a serious economic impact on our business. That’s another factor fleets need to consider.”

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