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Title: NO x emissions from diesel passenger cars worsen with age

Commonly, the NO x emissions rates of diesel vehicles have been assumed to remain stable over the vehicle's lifetime. However, there have been hardly any representative long-term emission measurements. Here we present real-driving emissions of diesel cars and light commercial vehicles sampled on-road over 15 years in Zurich/Switzerland. Results suggest deterioration of NO x unit emissions for Euro 2 and Euro 3 diesel technologies, while Euro 1 and Euro 4 technologies seem to be stable. We can exclude a significant influence of high-emitting vehicles. NO x emissions from all cars and light commercial vehicles in European emission inventories increase by 5-10% accounting for the observed deterioration, depending on the country and its share of diesel cars. Finally, we suggest monitoring the stability of emission controls particularly for high-mileage light commercial as well as heavy-duty vehicles.
 [1] ;  [2]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. International Institute for Applied Systems Analysis, Laxenburg (Austria)
Publication Date:
Report Number(s):
Journal ID: ISSN 0013-936X
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Environmental Science and Technology
Additional Journal Information:
Journal Volume: 50; Journal Issue: 7; Journal ID: ISSN 0013-936X
American Chemical Society (ACS)
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Country of Publication:
United States
30 DIRECT ENERGY CONVERSION; real-driving emissions; diesel cars; light commercial vehicles; NOx
OSTI Identifier: