Real-driving emissions from diesel passenger cars measured by remote sensing and as compared with PEMS and chassis dynamometer measurements - CONOX Task 2 report
In this study more than 200,000 emission data records for diesel passenger cars from remote sensing measurements carried out in Spain, Sweden, Switzerland and United Kingdom 2011-2017, were pooled to analyze particularly the real-world NOX emission performance of Euro 5 and Euro 6 cars.
The results show that average NOX emissions for diesel cars (by Euro class, make, engine family) as measured by remote sensing agree well with on-board emission (PEMS) measurements. Thus, remote sensing has proven a powerful tool for market surveillance and for complementing conventional real-world emission test methods.
The study shows that real-world NOX emissions from diesel cars remain virtually unchanged from Euro 1 to Euro 5, meaning that in real-world driving the average European diesel Euro 5 car emits 5-6 times more NOX in excess of the standard. Euro 6 diesel cars emit on average about half as much NOx as Euro 5, still Euro 6 emits on average about 5 times more NOx in excess of the standard. Ambient temperature has a strong effect on the emissions.
The data also demonstrates that the introduction of diesel particulate filters along with the Euro 5 emission standard has been very effective in reducing real-world PM emissions.