Some people have the impression that air pollution by NOx (nitrogen oxides) in Germany is as high as never before. In fact, the opposite is the case.
According to figures from the Federal Environmental Agency, NOx emissions in Germany fell by a total of around 60 percent between 1990 and 2017 – and emissions by road traffic by no less than around 70 percent. One major reason for this is technical innovations in commercial vehicles and passenger cars, and especially in recent years, further development of the diesel engine.
This extends from exhaust gas recirculation, NOx absorber catalytic converters and selective catalytic reduction (SCR) to a close-coupled emission control system in the latest engine generation.
Considerable resources have been devoted to the further development of diesel technology in recent years. At Daimler alone, we have invested three billion euros in our new diesel engines. The result is that since April 2016, Mercedes-Benz has already had diesel cars on the market that technically meet the more stringent EU emission limits that came into force for new models from September 1, 2017 as part of the RDE requirements (Stage 1). This has been confirmed by various tests conducted by independent organisations. Mercedes-Benz has been switching over its product range systematically to the new generation of diesel engines since.
Vehicles with latest-generation diesel engines also have low NOx emissions on the road.
The German automobile club ADAC recently stated the following relating to the nitrogen emissions of diesel vehicles by different manufacturers: "Euro-6d-TEMP diesels emit 76 percent less NOx on average than Euro-6b diesels, and 85 percent less than Euro-5 diesels. Random sample measurements on the road have shown that the emissions reduction of good Euro-6d-TEMP diesels compared with average Euro 5 diesels is as high as 95 to 99 percent".
The new Mercedes-Benz diesel engines are now available from the compact to the luxury class, and all new diesel cars available for order from Mercedes-Benz meet at least the Euro 6 d-TEMP emissions standard. Moreover, numerous Mercedes-Benz models already meet the even more stringent (owing to lower measuring tolerances) Euro 6d standard. This will not become mandatory for new models until January 1, 2020, and one year later for other vehicles.
More rapid replacement of the older vehicle population with these vehicles is an effective way to reduce NOx emissions in road traffic still further.