· Denoxtronic improves diesel engine's efficiency

· Focus on Euro 6 and Tier 2 Bin 5 emissions standards

Thanks to its superior energy balance, the diesel is already an eco-friendly engine, characterized by low consumption and CO2 emissions. Apart from further developing common-rail injection systems to make diesel engines more efficient and low in emissions, Bosch is focusing on the Denoxtronic exhaust-gas treatment system in order to reduce nitrogen-oxide emissions in passenger cars and light trucks. In doing this, Bosch is on the one hand creating the conditions that will allow diesel engines to comply with very strict emissions standards, such as Euro 6 in Europe or Tier 2 Bin 5 in the United States. On the other hand, this exhaust-gas treatment system will also allow the efficiency of the diesel engine to be further improved in the future.

Reduction of NOx emissions
With emission limits becoming ever tighter, the powerful diesel engines in the heavy passenger cars of the future will need an SCR catalyst (selective catalytic reduction) to reduce nitrogen-oxide (NOx) emissions. The transition from Euro 5 to Euro 6, for example, calls for a more than 50 percent reduction in NOx emissions. To meet this requirement, Bosch has adapted its Denoxtronic to the requirements of the passenger car. Denoxtronic has been successfully used in commercial vehicles since 2004. Together with the SCR catalyst, this exhaust-gas treatment system transforms any nitrogen oxide in the exhaust gas into harmless steam and nitrogen. It does this by injecting a reagent into the exhaust stream – a urea-water solution known as AdBlue. The metering system, which is networked with the engine electronics, precisely aligns the amount of AdBlue injected with engine parameters such as operating temperature and engine speed. This allows NOx emissions to be reduced by as much as 85 percent. Bosch has supplied several automakers with this system, which comprises a metering module, the AdBlue tank with delivery module, and a control unit.

Greater efficiency in the future
When developing future engine designs, Denoxtronic offers additional possibilities for further improving the diesel engine's efficiency. Any increase in engine efficiency goes hand in hand with an increase in nitrogen-oxide emissions, which are limited by law. Thanks to SCR exhaust-gas treatment with Denoxtronic, nitrogen-oxide emissions in the exhaust can be reduced. The efficiency of the diesel engine can be increased and fuel consumption reduced. Depending on application, the consumption of a Euro 6-compliant engine can be reduced by between five and seven percentage points.

Diesel vehicles equipped with Denoxtronic are already available in the European and U.S. markets. In Europe, they fulfill the Euro 6 emissions standard, planned for 2014. In addition, they comply with the U.S. emission limits set by the Environmental Protection Agency (EPA) and the California Air Resources Board (CARB), which means that they satisfy the emissions standards of all 50 U.S. states.

The Bosch Group is a leading global supplier of technology and services. In the areas of automotive and industrial technology, consumer goods, and building technology, some 275,000 associates generated sales of 38.2 billion euros in fiscal 2009. The Bosch Group comprises Robert Bosch GmbH and its more than 300 subsidiaries and regional companies in over 60 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for growth. Each year, Bosch spends more than 3.5 billion euros for research and development, and applies for some 3,800 patents worldwide. With all its products and services, Bosch enhances the quality of life by providing solutions which are both innovative and beneficial. The company was set up in Stuttgart in 1886 by Robert Bosch (1861-1942) as “Workshop for Precision Mechanics and Electrical Engineering.” The special ownership structure of Robert Bosch GmbH guarantees the entrepreneurial freedom of the Bosch Group, making it possible for the company to plan over the long term and to undertake significant up-front investments in the safeguarding of its future. Ninety-two percent of the share capital of Robert Bosch GmbH is held by Robert Bosch Stiftung GmbH, a charitable foundation. The majority of voting rights are held by Robert Bosch Industrietreuhand KG, an industrial trust. The entrepreneurial ownership functions are carried out by the trust. The remaining shares are held by the Bosch family and by Robert Bosch GmbH. Additional information can be accessed at www.bosch.com.

PI6749 - September 2009