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100,000-Mile Evaluation of Transit Buses Operated on Biodiesel Blends (B20)
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 16, 2006 by SAE International in United States
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Nine identical 40-ft. transit buses were operated on B20 and diesel for a period of two years - five of the buses operated exclusively on B20 (20% biodiesel blend) and the other four on petroleum diesel. The buses were model year 2000 Orion V equipped with Cummins ISM engines, and all operated on the same bus route. Each bus accumulated about 100,000 miles over the course of the study. B20 buses were compared to the petroleum diesel buses in terms of fuel economy, vehicle maintenance cost, road calls, and emissions. There was no difference between the on-road average fuel economy of the two groups (4.41 mpg) based on the in-use data, however laboratory testing revealed a nearly 2% reduction in fuel economy for the B20 vehicles. Engine and fuel system related maintenance costs were nearly identical for the two groups until the final month of the study. Component replacements near the end of the study on one B20 bus caused average maintenance costs to be higher for the B20 group ($0.07 vs. $0.05 per mile). However, engine and fuel system maintenance costs varied widely from bus-to-bus so the $0.02 per mile average difference between the two groups is not statistically significant. There was no significant difference in miles between road calls. Analysis of B20 samples during the study period revealed early problems with fuel blending. There also were occasional fuel filter plugging events for the B20-fueled buses that were likely caused by out of specification biodiesel, however the exact cause could not be conclusively determined. Oil analysis results indicate no additional wear metals from the use of B20, with similar rates of TBN and ZDDP decay. Soot levels in the lubricant were significantly lower for the B20 vehicles. Laboratory chassis emissions tests comparing the in-use B20 and petroleum diesel on the CSHVC cycle showed reductions in all measured pollutants, including a reduction in nitrogen oxides.
- Lou Ha - Regional Transportation District
- Howard L. Fang - Cummins, Inc.
- Kenneth Proc - National Renewable Energy Laboratory-U.S. Department of Energy
- Robb Barnitt - National Renewable Energy Laboratory-U.S. Department of Energy
- R. Robert Hayes - National Renewable Energy Laboratory-U.S. Department of Energy
- Matthew Ratcliff - National Renewable Energy Laboratory-U.S. Department of Energy
- Robert L. McCormick - National Renewable Energy Laboratory-U.S. Department of Energy
CitationProc, K., Barnitt, R., Hayes, R., Ratcliff, M. et al., "100,000-Mile Evaluation of Transit Buses Operated on Biodiesel Blends (B20)," SAE Technical Paper 2006-01-3253, 2006, https://doi.org/10.4271/2006-01-3253.
SAE 2006 Transactions Journal of Fuels and Lubricants
Number: V115-4; Published: 2007-03-30
Number: V115-4; Published: 2007-03-30
- United States Environmental Protection Agency “A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions.” Draft Technical Report, EPA420-P-02-001 2002
- Sheehan J. Camobreco V. Duffield J. Graboski M. Shapouri H “An Overview of Biodiesel and Petroleum Diesel Life Cycles.” National Renewable Energy Laboratory NREL/TP-580-24772 May 1998
- Graboski M. McCormick R. “Combustion of Fat and Vegetable Oil Derived Fuels in Diesel Engines.” Prog. Energy Combust. Sci. 24 1998 125 164
- Bickel K. Strebig K “Soy-Based Diesel Fuel Study.” Final report to Legislative Commission on Minnesota Resources and Minnesota Soygrowers Association 2000
- Chase C.L. Peterson C.L. Lowe G.A. Mann P. Smith J.A. Kado N.Y. “A 322,000 Kilometer (200,000 Mile) Over the Road Test with HySEE Biodiesel in a Heavy Duty Truck.” SAE Technical Paper No. 2000-01-2647 2000
- http://www.stm.info/English/info/a-biobus-final.pdf May 2003
- Fraer R. Dinh H. Proc K. McCormick R.L. Chandler K. Buchholz B. “Operating Experience and Teardown Analysis for Engines Operated on Biodiesel Blends (B20).” SAE Technical Paper No. 2005-01-3641 2005
- Dtn Energy's Alternative Fuels Index 4 2006 2
- McCormick R.L. Alleman T.L. Ratcliff M. Moens L. Lawrence R. “Survey of the Quality and Stability of Biodiesel and Biodiesel Blends in the United States in 2004.” National Renewable Energy Laboratory NREL/TP-540-38836 October 2005
- Tarandjiiska, R.B. Marekov, I.N. Nikolova-Damyanova, B.M. Amidzhin, B.S. “Determination of Triacylglycerol Classes and Molecular Species in Seed Oils with High Content of Linoleic and Linolenic Fatty Acids” J. of the Sci. of Food and Agriculture 24 1996 403 410
- Active Standard: D1319-03e1 “Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption” ASTM International West Conshohocken, PA www.astm.org
- United States Environmental Protection Agency “The Effect of Cetane Number Increase Due to Additives on NO x Emissions from Heavy-Duty Highway Engines” Final Technical Report, EPA420-R-03-002 February 2003
- McCormick, R.L. Hayes, R.R. Williams, A. Ireland, J. “Effect of Biodiesel Blends on Vehicle Emissions” Milestone Report National Renewable Energy Laboratory NREL/MP-540-40554 October 2006