Airborne emissions

Besides carbon dioxide and water vapor, automobile exhaust emissions include carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbons (HC). Diesel vehicles have the same emissions plus particulates. Vehicle emissions have a significant impact on air quality, especially in cities with heavy traffic.

In recent years, DaimlerChrysler has reduced the various types of emissions across its passenger-car range with the help of improved engine designs and highly efficient emission control systems. Since 1995, for example, NOx emissions have been cut by about 70 percent and diesel particulate emissions by more than 95 percent. Over the course of the past decade, the Group has also succeeded in dramatically reducing emissions of nitrogen oxides, hydrocarbons and particulates in its commercial vehicles by improving the control of combustion processes in engines and optimizing carburetion. The aim now is to apply state-of-the-art technologies to achieve further reductions and thus be able to comply as far in advance as possible with future emission limits in Europe, Asia and the U.S.

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The EU is currently preparing to introduce stricter emission limits for diesel and gasoline-powered vehicles, especially for nitrogen oxides (NOx) and particulates. The introduction of new emission limits for passenger cars (Euro 5) is planned for September 1, 2009, with Euro 6 to follow in 2014.

In order to combine all technical solutions for reducing diesel engine emissions into an optimized package, DaimlerChrysler is implementing a multi-staged plan that includes the following points:

Since the summer of 2005, all Mercedes-Benz diesel passenger cars sold in Germany, Austria, Switzerland and the Netherlands have been equipped with particulate filters as standard. In addition, Mercedes-Benz offers maintenance-free retrofitting systems for reducing particulate emissions in all C-Class and E-Class models with four-cylinder diesel engines and in M-Class models with five-cylinder diesel engines.

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The new smart fortwo cdi already complies with the requirements (Euro 4), even without a diesel particulate filter. In addition, the smart fortwo cdi is being equipped with a diesel particulate filter (open system) as standard in Germany, Italy and Switzerland.

Starting in 2008, the fortwo cdi will be offered with a closed system. Because it is incorporated into the engine control system, the closed system basically permits an even higher reduction of particulates in the exhaust than an open particulate filter system.

In the BLUETEC system, DaimlerChrysler brings together various technical features for reducing all relevant emission components in diesel passenger cars. The system includes an oxidizing catalytic converter and a diesel particulate filter, as well as innovative technologies for reducing nitrogen oxide emissions (either an enhanced DeNOX storage catalytic converter with an SCR catalytic converter, or the injection of an additive known as AdBlue). The AdBlue dilute urea solution is used as part of the selective catalytic reduction (SCR) process, which transforms nitrogen oxides into molecular nitrogen and water. This is currently the most effective method for exhaust gas treatment, and it can reduce nitrogen oxide emissions by up to 80 percent. DaimlerChrysler was the first passenger car manufacturer in the world to introduce this technology on the market: In October 2006 it launched the Mercedes-Benz E 320 BLUETEC (with a DeNOX storage catalytic converter and an SCR catalytic converter) on the North American market – just in time for the introduction of low-sulfur diesel fuel in the United States. A fuel consumption figure of 6.7 liters per hundred kilometers makes the E 320 BLUETEC one of the most economical vehicles in its class in the United States. Starting in 2008, three other V6 BLUETEC models will be offered on the U.S. market – in the R-Class, the M-Class and the GL-Class. The technology is currently being adapted to European market requirements and further Mercedes-Benz models. The market launch is scheduled for 2008.

At the Geneva Motor Show 2007, Mercedes-Benz presented its Vision C 220 BLUETEC, which demonstrated how to comply with the Euro 6 emission limits. Euro 6 will apply to all new vehicles in Europe starting in 2015.

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Low-emission commercial vehicles. Thanks to the innovative BLUE-TEC diesel technology, DaimlerChrysler commercial vehicles comply not only with the Euro 4 emission limits but also with the Euro 5 limits that will not go into effect until October 2009. Here, the NOx emissions can be cut by more than 80 percent in conjunction with a reduction in fuel consumption.

In order to comply with EPA 07, the emission limits that will apply to commercial vehicles in the U.S. from 2007 on, DaimlerChrysler has decided to use exhaust gas recirculation with an additional particulate filter. The future emission limits in the U.S. and Japan (EPA 10 and JP 09 respectively) will be met with SCR technology.