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Projects: Projects for Investigator
Reference Number EP/S019375/1
Title Texas TTI Visiting Scholarship: Targeting the Bad Emitting Vehicles
Status Completed
Energy Categories Energy Efficiency(Transport) 10%;
Not Energy Related 90%;
Research Types Basic and strategic applied research 50%;
Applied Research and Development 50%;
Science and Technology Fields PHYSICAL SCIENCES AND MATHEMATICS (Physics) 50%;
ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering) 50%;
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Dr K Ropkins
No email address given
Institute for Transport Studies
University of Leeds
Award Type Standard
Funding Source EPSRC
Start Date 01 May 2019
End Date 30 November 2020
Duration 19 months
Total Grant Value £49,895
Industrial Sectors Transport Systems and Vehicles
Region Yorkshire & Humberside
Programme NC : Engineering
Investigators Principal Investigator Dr K Ropkins , Institute for Transport Studies, University of Leeds (100.000%)
  Industrial Collaborator Project Contact , Texas A & M University, USA (0.000%)
Web Site
Abstract We know some vehicles are bad emitters, i.e., they are continuous or intermittent high emitters of one or more priority pollutant. We do not know exact numbers, but we suspect some are poorly engineered vehicles, some are deliberately tampered vehicles and some are incorrectly or unmaintained vehicles (1). Vehicle Emissions Remote Sensing Systems (VERSSs) provide a measure of across-fleet emissions and have often been used to generate '20% of fleet cause 80% of emissions' headlines (see e.g. 2,3). However, they give a 'snap-shot' measurement that most likely misassigns both occasional high emissions from otherwise properly functioning emissions systems as bad vehicles, and better measurements from vehicles with failing emissions systems as good vehicles (4). The unknown scale of such false-negatives and false-positives prevents us from using such techniques to do what we would most like to, namely to reliably target individual vehicles.Elsewhere, others have already begun to look at alternative techniques, for example both California ARB and Texas COG have instigated work on other passing vehicle emissions monitoring methods like OHMS and PEAQS (5,6). Both are high-volume active air sampling methods that trade by comparison to VERSSs, reduced fleet capture rates for longer duration but therefore more representative measures of passing vehicle emissions. While these techniques improve confidence, they are still limited by fixed-point deployment, limiting our ability to engine-load profile emissions.Car-chaser vehicle that include on-board monitors configurated to measure the emissions of other followed vehicles, although out of favour for conventional monitoring activities, could provide us with a better option to target and optimise evidence gathering elements of our efforts to identify and take action against the highest emitting vehicles on our roads. Therefore, the objectives here are two-fold: (1) To explore options to enhance our understanding of high emitters, through the focused analysis of US EPA emission archives, which TTI have access to via established Research Collaboration Agreement. And (2), To repurpose and redeploy conventional in-vehicle emissions measurement systems for car-chaser work focused on the characterisation of followed-vehicle emissions as good or bad, with an aim of scoping the potential for such systems for a role in (near-term) future emissions reduction policy.References: (1) Ligterink, N., 2017. Real-world Vehicle Emissions. International Transport Forum Discussion Paper 2017-06. (2) Pujadas, M., Dominguez-Saez, A. and De la Fuente, J., 2017. Real-driving emissions of circulating Spanish car fleet in 2015 using RSD Technology. Science of the Total Environment, 576, pp.193-209. (3) Wang, J.M., Jeong, C.H., Zimmerman, N., Healy, R.M., Wang, D.K., Ke, F. and Evans, G.J., 2015. Plume-based analysis of vehicle fleet air pollutant emissions and the contribution from high emitters. Atmospheric Measurement Techniques, 8(8), p.3263. (4) Huang, Y., Organ, B., Zhou, J.L., Surawski, N.C., Hong, G., Chan, E.F. and Yam, Y.S., 2018. Remote sensing of on-road vehicle emissions: Mechanism, applications and a case study from Hong Kong. Atmospheric Environment. 182, 58-74. (5) Bishop, G.A., Hottor-Raguindin, R., Stedman, D.H., McClintock, P., Theobald, E., Johnson, J.D., Lee, D.W., Zietsman, J. and Misra, C., 2015. On-road heavy-duty vehicle emissions monitoring system. Environmental science & technology, 49(3), pp.1639-1645. (6) Smith, J.D., Ham, W., Burnitzki, M., Downey, S., Howard, C., Quiros, D., Hu, S., Chernich, D., Huai. 2018. Quantification of HD in-use Vehicles using the Portable Emissions AcQuisition System (PEAQS). 28th CRC Real World Emissions Workshop March, 18th-21st, 2018, Anaheim, California, US.
Publications (none)
Final Report (none)
Added to Database 19/08/19