Emission Control Science and Technology

, Volume 4, Issue 4, pp 279–288 | Cite as

Evaluation of Greenhouse Gas Emission Benefits of Vehicle Speed Limiters on On-Road Heavy-Duty Line-Haul Vehicles

  • Phuong HoEmail author
  • David Quiros
  • William Robertson
  • Chris Ruehl
  • Wayne Sobieralski
  • Robert Ianni
  • Donald Chernich
  • Renee Littaua


Vehicle speed limiters (VSLs) are one of the strategies for reducing greenhouse gas (GHG) emissions from heavy-duty vehicles; they work by limiting peak vehicle speed. In the Federal Phase 2 Rule—GHG Emissions and Fuel Efficiency Standards for Medium- and Heavy-duty Engines and Vehicles, the greenhouse gas emission model (GEM) includes emission reduction credits for vehicles equipped with tamper-proof VSLs set at 55 to 65 miles per hour (mph). In this study, on-road testing of three class 8 combination tractor-trailers was conducted at various cruising speeds between 45 and 78 mph under steady conditions to evaluate the emission impacts of VSLs on heavy-duty vehicles. The three tested trucks were equipped with model year (MY) 2007 and newer engines and low-rolling-resistance tires on both the tractors and trailers. One truck was tested with a combined test weight of 35,000 lb and each of the other two trucks was tested with a combined test weight of 76,000 lb. A portable emission measurement system (PEMS) was used to measure carbon dioxide (CO2) emissions, and results showed that distance-based CO2 emission rates were dependent on both vehicle speed and engine revolutions per minute (rpm). Compared to average CO2 emission rates of approximately 1524 grams per mile (g/mile) at 78 mph for these test trucks, average CO2 emission rates at 51 mph were ~ 36% lower (approximately 978 g/mile) and represented the minimum distance-based (i.e., in g/mile) CO2 emission rates within the speed range evaluated for the three test trucks. Specifically, when decreasing speeds from 78 to 55 mph, CO2 emissions were between 0.7 and 2.6% lower per mph reduced. The emission benefits of using VSLs estimated from data in this study agree with the emission credits in the federal GEM. In addition, the quadratic relationship between CO2 emissions and vehicle speed measured for the three test trucks was used to corroborate updates to CARB’s EMission FACtor (EMFAC) 2017 model that were based on dynamometer testing; the measured trends from this VSL study support the predictions in that model.


Vehicle speed limiter Greenhouse gas CO2 emission Heavy-duty vehicle Class 8 truck 



The authors thank the Monitoring and Laboratory Division of the California Air Resources Board (CARB) (Dr. Walter Ham, Dr. Cody Howard, and Mr. Arlmon Vanzant) for their testing and data analysis support and the Emissions Compliance, Automotive Regulations, and Science Division of CARB (Mr. Shiyan Chen and Mr. Tai Sea Yen) for their test vehicle procurement effort. The authors also thank Ms. Kim Heroy-Rogalski, Dr. Tao Huai, Dr. Shaohua Hu, Dr. Sam Pournazeri, and Dr. John Collins for their valuable support on the project testing development and completion.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no competing interests.


The statements and opinions expressed in this paper are solely the authors’ and do not represent the official position of CARB. The mention of trade names, products, and organizations does not constitute endorsement or recommendation for use. CARB is a department of the California Environmental Protection Agency. CARB’s mission is to promote and protect public health, welfare, and ecological resources through effective reduction of air pollutants while recognizing and considering effects on the economy. CARB oversees all air pollution control efforts in California to attain and maintain health-based air quality standards.


  1. 1.
    North American Council for Freight Efficiency, Speed limiters save money and fuel without significant productivity loss. Online available from In 2011
  2. 2.
    Ang-Olson, J.; Schroeer, W. Energy efficiency strategies for freight trucking: potential impact on fuel use and greenhouse gas emissions. Transportation Research Record: Journal of the Transportation Research Board, Volume 1815. Paper No. 02–3877. In 2002Google Scholar
  3. 3.
    U.S. Department of Transportation Federal Motor Carrier Safety Administration, Research on the safety impacts of speed limiter device installations on commercial motor vehicles: phase II. In 2012Google Scholar
  4. 4.
    Transportation Research Board of the National Academies, Commercial truck and bus safety synthesis program – CTBSSP synthesis 16 – safety impacts of speed limiter device installations on commercial Trucks and Buses. In 2008Google Scholar
  5. 5.
    United States Environmental Protection Agency and Department of Transportation National Highway Traffic Safety Administration, Greenhouse gas emissions and fuel efficiency standards for medium- and heavy-duty engines and vehicle – phase 2, Final Rule. In 2016Google Scholar
  6. 6.
    Capps, G.; Franzese, O.; Knee, B.; Lascurain, M.; Otaduy, P. Class 8 heavy truck duty cycle project final report. Oak Ridge National Laboratory. ORNL/TM-2008/122. In 2008Google Scholar
  7. 7.
    California Air Resources Board, Mobile source emissions inventory. Online available from
  8. 8.
    Society of Automotive Engineers (SAE) International, Road load measurement and dynamometer simulation using coastdown techniques, SAE J1263, revised September 03, 2010Google Scholar
  9. 9.
    Society of Automotive Engineers (SAE) International, Road load measurement using onboard anemometry and coastdown techniques, SAE J2263, revised December 12, 2008Google Scholar
  10. 10.
    Trucking efficiency (North American Council for Freight Efficiency and the Carbon War Room), confidence report: electronically controlled transmissions. Online available from In 2014Google Scholar
  11. 11.
    Ahlawat, R.; Bredenbeck, J.; Ichige, T. Estimation of road load parameters via on-road vehicle testing. Online available from
  12. 12.
    Clark, N.; Kern, J.; Atkinson, C.; Nine, R. Factors affecting heavy-duty diesel vehicle emissions. J. Air Waste Manage. Assoc., 52:1, 84–94, DOI: In 2002, 2011
  13. 13.
    Farkas, S. Fuel efficiency in truck industry. Scientific Bulletin of the “Petru Maior” University of Tîrgu Mureş, Vol. 7 (XXIV), no. 2, ISSN 1841–9267. In 2010Google Scholar
  14. 14.
    Berg, T. Gearing up for fuel economy. HDT Truckinginfo, June 2007. Online available from
  15. 15.
    Johnson, S. (University of Arkansas); Murray, D. (American Transportation Research Institute). Empirical analysis of truck and automobile speeds on rural interstates: impact of posted speed limits. Online available from In 2009
  16. 16.
    Driving the limits of fuel efficiency. Volvo trucks driver’s digest, November 2011Google Scholar
  17. 17.
  18. 18.
    United States Environmental Protection Agency, Greenhouse gas emissions model (GEM) for medium- and heavy-duty vehicle compliance. Online available from

Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.California Air Resources BoardSacramentoUSA
  2. 2.Mobile Source Control DivisionCalifornia Air Resources BoardSacramentoUSA

Personalised recommendations