The introduction of particulate and oxides of nitrogen (NOx) after-treatment controls on heavy-duty vehicles has spurred the need for fleet emissions data to monitor their reliability and effectiveness. The University of Denver has developed a new method for rapidly measuring heavy-duty vehicles for gaseous and particulate fuel specific emissions. The method was recently used to collect 3088 measurements at a Port of Los Angeles location and a weigh station on I-5 in northern California. The weigh station NOx emissions for 2014 models are 73% lower than 2010 models (3.8 vs 13.9 gNOx/kg of fuel) and look to continue to decrease with newer models. The Port site has a heavy-duty fleet that has been entirely equipped with diesel particulate filters since 2010. Total particulate mass and black carbon measurements showed that only 3% of the Port vehicles measured exceed expected emission limits with mean gPM/kg of fuel emissions of 0.031 0.007 and mean gBC/kg of fuel emissions of 0.020 0.003. Mean particulate emissions were higher for the older weigh station fleet but 2011 and newer trucks gPM/kg of fuel emissions were nevertheless more than a factor of 30 lower than the means for pre-DPF (2007 and older) model years.
Bishop, G. A., Hottor-Raguindin, R., Stedman, D. H., McClintock, P., Theobald, E. d., Johnson, J. D., ... Misra, C.
citation count
47
complete list of authors
Bishop, Gary A||Hottor-Raguindin, Rachel||Stedman, Donald H||McClintock, Peter||Theobald, Ed||Johnson, Jeremy D||Lee, Doh-Won||Zietsman, Josias||Misra, Chandan
