URBANDALE, Iowa - The Iowa Soybean Association has partnered with Iowa Central Community College, Decker Truck Line Inc., Caterpillar Inc., the National Biodiesel Board and the USDA to conduct a unique field documentation study dubbed the “Two Million Mile Haul.” This is a comprehensive study to examine the benefits of a 20 percent soy biodiesel blend (B20) in an over-the-road trucking company. Iowa Central is responsible for collecting and analyzing engine performance data as well as periodic in-house testing of the petroleum and B20 blend fuels for purity and consistency. Additionally, the study examines the effects of various fuel additives on the cold-flow properties of biodiesel blended with the new 2007 Ultra-Low Sulfur Diesel (ULSD). The studies are focusing primarily on the cloud, plug and pour points.

Summary of Results
As of April 2007, Decker logged more than half a million miles in the study using 10 trucks in the control group (fueled with 100 percent #2 petroleum diesel) and nine trucks in the B20 test group (fueled with 20 percent biodiesel, 80 percent petroleum diesel). It was found that driver-to-driver variability in fuel consumption within each group is two to three times greater than the overall difference in fuel consumption between the two groups. Results showed a slight decrease in fuel efficiency in the B20 group through the winter driving season. Average fuel consumption for the control group was 6.01 miles per gallon (mpg) while average consumption for the B20 group was 5.80 mpg, or a 3.5 percent reduction. This value is not statistically significant (p = 0.125).

Winter driving produced relatively few problems regarding cold-flow issues. Fuel for both groups was treated with a commercial fuel additive and #1 diesel (40 percent blend) was used for a brief time during a severe cold snap. No drivers experienced fuel gelling problems.

Conclusions
Researchers feel that the first quarter of the study has been a success. They found no significant difference in fuel consumption between the two groups and were able to get through the winter driving season without any major complications. The study also found that the driver-to-driver variability is larger than the slight difference in fuel efficiency observed to this point and an entire four-season driving cycle should be completed before conclusions can be made on fuel efficiency. Regarding cold-flow issues, there were no fuel gelling problems during the cold snaps and the plugged filters that did occur were not related to fuel quality as outlined by ASTM-D6751 standards.

For more information on the first quarter results of the Two Million Mile Haul, visit www.iowacentral.com/mathscience/science/programs/biofuels/research_collaboration.htm.