Implications of Driving Style and Road Grade for Accurate Vehicle Activity Data and Emissions Estimates

Real-world vehicle operating mode data (2.5 million 1Hz records), collected by instrumenting the vehicles of 82 volunteer drivers with on-board diagnostics (OBD) datalogger and global positioning system (GPS) while they drove their routine travel routes, were analyzed to quantify vehicle emissions estimate error due to road grade and driving style in rural, hilly Vermont. The Environmental Protection Agency (EPA) Motor Vehicle Emission Simulator (MOVES)2010b was used to estimate running exhaust emissions associated with measured vehicle activity. Changes in vehicle specific power (VSP) and MOVES operating mode (OpMode) due to proper accounting for real-world road grade indicated emission rate errors between 10-48%, depending on pollutant, chiefly because grade-related changes in VSP could shift activity by as many as six OpModes, depending on road type. The correct MOVES OpMode assignment was made only 33-55% of the time when road grade was not included in the VSP calculation. Driving style of individual drivers was difficult to assess due to unknown traffic operations data, but the largest differences between individual drivers was observed on rural restricted roads. The study results suggest the importance of (a) measuring and incorporating real-world road grade in order to correctly assign MOVES emission rates; and (b) developing a driving style typology to account for error in the MOVES emissions estimates due to driver variability.

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• Supplemental Notes:
  • This paper was sponsored by TRB committee ADC20 Transportation and Air Quality.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Sentoff, Karen M
  • 0000-0002-1108-6474
  • Aultman-Hall, Lisa
  • Holmén, Britt A
  • 0000-0003-3020-4293
• Conference:
  • Transportation Research Board 94th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2015-1-11 to 2015-1-15
• Date: 2015

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 13p
• Monograph Title: TRB 94th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Accuracy; Driver performance; Drivers; Estimating; Highway grades; Pollutants; Vehicle performance
• Identifier Terms: Motor Vehicle Emission Simulator (MOVES)
• Geographic Terms: Vermont
• Subject Areas: Environment; Highways; I15: Environment;

Filing Info

• Accession Number: 01554185
• Record Type: Publication
• Report/Paper Numbers: 15-4702
• Files: PRP, TRIS, TRB, ATRI
• Created Date: Feb 26 2015 9:49AM