Modern gasoline-fueled personal cars with direct-injection technology exhibiting high emissions of nitrogen oxides in new laboratory tests.
Researchers at Institute of Transport Economics in Norway (TØI) and VTT in Finland have tested various vehicles by applying test-cycles which represent real traffic, and conditions that to most possible extent correspond to the actual use of the vehicle.
The new results widely confirm earlier findings: Heavy duty vehicles with Euro VI-engines have low emissions of nitrogen oxides (NOx) in real traffic situations, while diesel-fueled Euro 6-passenger cars have high emissions compared to the emission limits in the emission legislation.
The testing also revealed remarkable results for modern gasoline-fueled personal cars with direct-injection technology; they exhibit higher emissions of NOx in the laboratory tests than the emission legislation states.
The results are presented in a new report that is published as part of the measurement program EMIROAD (EMIssions from ROAD transport vehicles). The program focuses on exhaust emissions from modern passenger cars and heavy duty vehicles and is a cooperation of TØI and the Norwegian Public Roads Administration.
In the EMIROAD measurement program vehicles are tested in the laboratory by applying test-cycles which represent real traffic. For example, the program investigates “local emission factors” which include nitrogen oxides (NOx) and particulate matter (PM). Furthermore, the emission of greenhouse gases (CO2 in particular) is investigated.
These findings call for a thorough redefinition of “normal use” in the type-approval directive, and whether it could be possible to introduce not-to-exceed-values that should not be exceeded in any driving condition.
The report is written in Norwegian but you can read more about the findings in the English summary: Emission from vehicles with Euro 6/VI technology. Results from the measurement program in EMIROAD 2015. TØI Report 1506/2016
Authors: Christian Weber and Astrid H. Amundsen
Astrid H. Amundsen