Evaluation of Heavy- and Medium-Duty On-Road Vehicle Emissions in California's South Coast Air Basin
Publication Date
2018
Document Type
Article
Organizational Units
Chemistry and Biochemistry
Keywords
Atmospheric chemistry, Emissions, Pollutants, Heavy-duty diesel trucks
Abstract
Emission measurements were collected from heavy-duty (HDVs) and medium-duty vehicles (MDVs) at the Peralta weigh station long-term measurement site near Anaheim, CA in 2017. Two Fuel Efficiency Automobile Test units sampled elevated and ground-level exhaust vehicles totaling 2,315 measurements. HDVs (1844 measurements) exhibited historical reductions in fuel specific oxides of nitrogen (NOx) from the 2008 measurements (55%) with increased use of exhaust gas recirculation and selective catalytic reduction systems. However, as these technologies have aged, the in-use benefits have declined. Infrared %opacity measurements of tailpipe soot decreased 14% since 2012 with increased diesel particulate filter (DPF) use, DPF longevity and fleet turnover. 63% of the HDV fleet in 2017 was chassis model year 2011+ compared to only 12% in 2012. The observed MDV fleet (471 measurements) was 1.4 years older than the HDV fleet with average NOx 14% higher. A significant reduction in MDV NOx occurred approximately 2 model years prior to similar HDV reductions (2014 versus 2016 chassis model year). MDV chassis model years 2014+ were able to meet their corresponding NOx laboratory certification standards in-use, whereas HDVs remain slightly above this threshold. Similar MDV NOx emission trends were also observed in data previously collected in Chicago, IL.
Copyright Statement / License for Reuse
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License
Rights Holder
Molly J. Haugen, Gary A. Bishop, Arvind Thiruvengadam, Daniel K. Carder
Provenance
Received from author
File Format
application/pdf
Language
English (eng)
Extent
38 pgs
File Size
586 KB
Publication Statement
This is an Accepted Manuscript for
Haugen, M. J.; Bishop, G. A.; Thiruvengadam, A.; Carder, D. K. (2018) Evaluation of Heavy- and Medium-Duty On-Road Vehicle Emissions in California's South Coast Air Basin. Environ. Sci. Technol., 52(22), 13298-13305. DOI: 10.1021/acs.est.8b03994.
Copyright held by the American Chemical Society. User is responsible for all copyright compliance.
Recommended Citation
Haugen, M. J.; Bishop, G. A.; Thiruvengadam, A.; Carder, D. K. (2018) Evaluation of Heavy- and Medium-Duty On-Road Vehicle Emissions in California's South Coast Air Basin. Environ. Sci. Technol., 52(22), 13298-13305. DOI: 10.1021/acs.est.8b03994.
DOI Link
https://doi.org/10.1021/acs.est.8b03994