United States Environmental Protection Agency Air and Energy Engineering Research Laboratory Research Triangle Park, NC 27711 Research and Development EPA/600/SR-93/214 January 1994 &EPA Project Summary Conceptual Designs for a New Highway Vehicle Emissions Estimation Methodology John T. Ripberger This report discusses conceptual de- signs from six contractors for a new highway vehicle emissions estimation methodology and summarizes the con- tractors' recommendations for improv- ing the emissions and activity factors in the emissions estimation process. The complete reports are included as appendices. EPA asked these contrac- tors to assist in developing ideas for a future improved methodology to esti- mate highway vehicle emissions. They were selected because of their experi- ence in working with mobile source emissions inventories. In general, the contractors suggest developing new modules within the emission estimation process to provide users with more detailed information on the causes of vehicle emissions. The essence of these suggestions is the need for more comprehensive inte- gration of data between the transporta- tion planning model and the emission factor model. The reports reinforced comments voiced by other experts for modal data and more responsive trans- portation models, although they did not identify totally new concepts not al- ready being considered by EPA re- search programs. This Project Summary was developed by EPA's Air and Energy Engineering Research Laboratory, Research Tri- angle Park, NC, to announce key find- ings of the research project that is fully documented in a separate report of the same title (see Project Report ordering information at back). Project Overview In April 1991, six tasks were awarded to look for new concepts that could poten- tially provide improved emission inventory estimates from highway vehicles in 5-10 years. Contractors were asked to submit their ideas for a new highway vehicle emis- sions estimation methodology. The request to the contractors was to determine if, because of changes in vehicle technolo- gies, transportation analysis tools, and sci- entific understandings, adoption of new concepts could provide significant advan- tages over existing methodologies. This project was a follow-on to the two high- way vehicle workshops held in the sum- mer of 1990 to solicit recommendations from emission inventory experts. The con- tractors (Alliance Technologies Corp., Desert Research Institute, E. H. Pechan & Associates, Inc., Radian Corp., Sierra Research, Inc., and Systems Applications International) were selected because of their experience in using and developing mobile source emission inventories for EPA and California. E. H. Pechan & As- sociates teamed with COMSIS Corpora- tion to address transport modeling recom- mendations. Ground rules for the study were that: 1) emission inventory estimates are used by EPA and states in models to determine the effectiveness of various con- trol strategies for achieving air quality stan- dards; 2) the methods now available for Printed on Recycled Paper ------- estimating emissions from highway ve- hicles will not be adequate for the new fuels, technologies, and transportation con- trol methods available in 5 to 10 years; and 3) this project is intended to begin the process of looking for an optimum meth- odology for estimating emissions and en- suring that the estimates meet future U.S. needs. The results of this effort should help produce better methods for estimat- ing emissions from highway vehicles. The time frame for implementing any new con- cepts is 5 - 10 years. This report summarizes the conceptual designs received in 1991 from six con- tractors. Their complete reports are in- cluded as appendices. In general, the con- tractors' reports suggest developing new modules within the emission estimation process to provide users with more de- tailed information on the causes of vehicle comprehensive integration of data between the transportation planning model and the emission factor model. To present the con- tractors' recommendations clearly and to avoid redundancy, this report combines their concepts and organizes them ac- cording to topic, rather than simply sum- marizing each contractor's conceptual de- sign separately. First, concepts on improv- ing emission factors are considered, fol- lowed by recommendations for improving activity factors, and ideas for organizing and coordinating the new emission and transportation models. As EPA develops its research program to prepare emission inventory models for the future, it is attempting to ensure that no promising new concepts are over- looked. This effort was to solicit ideas from contractors experienced in estimat- ing emissions from highway vehicles. For the most part, the reports did not identify any totally new concepts not already be- ing considered by EPA research programs. Most of the ideas were linked to existing procedures, requiring much costly data collection concerning vehicle emissions and operations on highway networks. The reports reinforced comments voiced by other experts for modal data and more responsive transportation models. 'U.S.Government Printing Office: 1994—550-067/80135 J. T. Ripberger is a Participant in the Earth Team Soil Conservation Service Volunteer Program assisting the U.S. EPA. Carl T. Ripberger is the EPA Project Officer (see below) The complete report, entitled "Conceptual Designs for a New Highway Vehicle Emissions Estimation Methodology," (Order No. PB94-120 128/AS; Cost: $36.50, subject to change) will be available only from: National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone: 703-487-4650 The EPA Author and Project Officer can be contacted at: Air and Energy Engineering Research Laboratory U.S. Environmental Protection Agency Research Triangle Park, NC 27711 United States Environmental Protection Agency Center for Environmental Research Information Cincinnati, OH 45268 Official Business Penalty for Private Use $300 BULK RATE POSTAGE & FEES PAID EPA PERMIT No. G-35 EPA/600/SR-93/214 ------- |