Energy End-Use Forecasting
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Analysis of In-Use Vehicle Emissions Using Data from State I/M Programs

Project Description

Since 1992 LBNL has compiled and analyzed data from vehicle emissions inspection and maintenance (I/M) programs managed in several states. This effort has involved compiling and analyzing I/M test results, remote sensing measurements, roadside pullover test results, and vehicle registration records. We have used these data to analyze various aspects of I/M programs in Arizona, California, Colorado, and Ontario, Canada, including estimate of emission reductions, the fraction of no-final-pass vehicles that continue to be driven in I/M areas, repeat failure rates, and aspects of motorist non-compliance with program requirements. All data sets have been quality controlled and analyzed for validity and internal consistency.

State I/M data also provide a rich resource on in-use vehicle emissions. The large number of vehicles tested can make up for several of the limitations of how the data were collected (inconsistent preconditioning, different test durations, etc.). Below are some of the analyses we have performed with state I/M data.

Project Staff

Tom Wenzel

Key Data

Publications

Evaluation of Inspection and Maintenance Programs

Wenzel, Thomas P., Brett C. Singer, Robert Slott, and Donald H. Stedman. "Short-term emissions deterioration in the California and Phoenix I/M programs." Accepted for publication in Transportation Research Part D. LBNL-52169.

Singer, Brett C. and Thomas P. Wenzel. 2003. "Estimated emission reductions from California's Enhanced Smog Check program." Environmental Science and Technology, 37:2588-2595. LBNL-52109.

Pollack, Alison, Till Stoeckenius, Cuong Tran, Tom Wenzel, Joel Schwartz, and Virginia McConnell, 2003. Performance Audit of the Colorado AIR program. Final report to the State of Colorado Office of the General Auditor. ENVIRON, International. June. (participation as an outside private consultant). Report

Wenzel, Tom, 2003. "Use of remote sensing measurements to evaluate vehicle emission monitoring programs: results from Phoenix, Arizona." Environmental Science and Policy, 6:153-166. LBNL-50995.

Eastern Research Group, Inc., 2002. Baseline Analysis of Enhanced I/M Compliance. Final report for the Arizona Department of Environmental Quality. June.

Eastern Research Group, Inc., 2002. Analysis of Historical Remote Sensing and I/M Emissions Data in Arizona. Final report for the Arizona Department of Environmental Quality. June.

Wenzel, Tom, 2001. "Evaluating the long-term effectiveness of the Phoenix IM240 program." Environmental Science and Policy, 4:377-389. LBNL-48008.

Wenzel, Tom, 2001. "Reducing emissions from in-use vehicles: an evaluation of the Phoenix inspection and maintenance program using test results and independent emissions measurements." Environmental Science and Policy, 4:359-376. LBNL-48007.

Wenzel, Tom, 2001. Can More Frequent Testing Improve I/M Program Effectiveness? Analysis of the Effect of Annual Testing in the Phoenix IM240 Program. Final report to Environmental Systems Products, Inc. Lawrence Berkeley National Laboratory, LBNL-47754. April. Report

Wenzel, Tom, 2000. Evaluation of the Effectiveness of Alternative Fast Pass, Fast Fail, and Retest Algorithms in the Phoenix IM147 Program. Final report to the Arizona Department of Environmental Quality. Lawrence Berkeley National Laboratory, LBNL-48006. October. Report

Wenzel, Tom and Robert Sawyer, 2000. Analysis of State Data on In-Use Emissions from Motor Vehicles: Review of Work Completed. Report to U.S. EPA. Lawrence Berkeley National Laboratory, LBNL-46816. September.

Wenzel, Tom, Brett Singer, Etan Gumerman, Robert Slott, and Robert Sawyer. 2000. Section III: Evaluation of the Enhanced Smog Check Program: A Report to the California Inspection and Maintenance Review Committee. Final report submitted to the California Inspection and Maintenance Review Committee. Lawrence Berkeley National Laboratory, LBNL-46117. June. Analysis | Report

Wenzel, Tom, 1999. Using Program Test Result Data to Evaluate the Phoenix I/M Program. Report to the Arizona Department of Environmental Quality. December. (prepared as an outside private consultant). Analysis | Report

Wenzel, Tom and Robert Sawyer, 1999. Emission Reduction Potential from Repairing Gross Emitters. Memo to James Bagian, US EPA. February 4. Analysis | Report

Wenzel, Tom and Robert Sawyer, 1998. Review of Sierra Research Report "Development of a Proposed Procedure for Determining the Equivalency of Alternative Inspection and Maintenance Programs". Report to US EPA. Lawrence Berkeley National Laboratory, LBNL-44045. September. Analysis | Report

Wenzel, Tom and Robert Sawyer. 1998. Analysis of a Remote Sensing Clean Screen Program in Arizona. Final report to U.S EPA. Lawrence Berkeley National Laboratory, LBNL-41918. June. Analysis | Report

Modeling High Emitter Vehicles

Wenzel, Tom and Marc Ross, 2003. "Comment on 'Statistical modeling of vehicle emissions from inspection/maintenance testing data: an exploratory analysis.'" Transportation Research Part D, 8:69-71. LBNL-48061.

Barth, Matthew, Feng An, Theodore Younglove, Carrie Levine, George Scora, Marc Ross, and Tom Wenzel. 1999. NCHRP Project 25-11: The Development of a Comprehensive Modal Emissions Model. Final report submitted to the National Cooperative Highway Research Program. LBNL-46116. November.

Wenzel, Tom and Marc Ross, 1998. "Characterization of Recent-Model High-Emitting Automobiles. " Society of Automotive Engineers Technical Paper 981414.

Barth, Matthew, Theodore Younglove, Tom Wenzel, George Scora, Feng An, Marc Ross, and Joseph Norbeck, 1997. "Analysis of Modal Emissions from a Diverse In Use Vehicle Fleet." Transportation Research Record 1587. National Academy Press, Washington: DC.

General Vehicle Emissions

Wenzel, Tom, Brett Singer, and Robert Slott, 2000. "Some issues in the statistical analysis of vehicle emissions." Journal of Transportation and Statistics, 3:2, 1-14. LBNL-46115. Paper

Ross, Marc, Rob Goodwin, Rick Watkins, Tom Wenzel, and Michael Q. Wang, 1998. "Real world emissions from conventional passenger cars." Journal of the Air and Waste Management Association, 48: 502-515.

Ross, Marc and Tom Wenzel, 1997. "Forum: The Few. The Failed. The Polluters," Marc Ross and Tom Wenzel, Technology Review, 100:6, August/September.

Ross, Marc and Tom Wenzel, 1997. "Real World Emissions from Conventional Passenger Cars," in Transportation, Energy, and Environment: How Far Can Technology Take Us?, edited by John DeCicco and Mark Delucchi. American Council for an Energy Efficient Economy, Washington: DC.

Wenzel, Tom and Marc Ross, 1996. "Emissions from Modern Passenger Cars with Malfunctioning Emissions Controls." Society of Automotive Engineers Technical Paper 960067.

Ross, Marc, Robert Goodwin, Rick Watkins, Michael Wang and Tom Wenzel, 1995. Real-World Emissions from Model Year 1993, 2000, and 2010 Passenger Cars. American Council for an Energy Efficient Economy and Lawrence Berkeley National Laboratory, LBL-37977. November.

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 Last Updated On: 8/19/04