title: NOx Emissions from Diesel Passenger Cars Worsen with Age.
abstract: 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. We suggest monitoring the stability of emission controls particularly for high-mileage light commercial as well as heavy-duty vehicles.
authors.affiliation: National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States.
authors.forename: Yuche
authors.initials: Y
authors.lastname: Chen
authors.affiliation: International Institute for Applied Systems Analysis, Schlossplatz 1, 2361 Laxenburg, Austria.
authors.forename: Jens
authors.initials: J
authors.lastname: Borken-Kleefeld
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D001334:Automobile Driving; D001336:Automobiles; D006801:Humans; D009589:Nitrogen Oxides / Q000032:analysis* / Q000737:chemistry; D013557:Switzerland; D013997:Time Factors; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D009589:Nitrogen Oxides; D001335:Vehicle Emissions