skip to main content

Title: NOx emissions from diesel passenger cars worsen with age

Commonly, the NOx 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 NOx 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. NOx 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:
OSTI Identifier:
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