Stuttgart, February 2011. By optimising the diesel engine, Mercedes-Benz has time and again been setting new milestones for the future of the internal combustion engine. With BlueTec and CDI BlueEFFICIENCY models, in particular, Mercedes-Benz engineers have succeeded in recent years in making the powerful and economical diesel engine as clean as the petrol engine. In 2010 all CDI BlueEFFICIENCY E-Class models with six-cylinder diesel power plant, for example, already meet the EU5 emission standard, and the BlueTEC model E 350 BlueTEC with urea injection even meets the future EU6 standard. Diesel-hybrid vehicles like the E 300 BlueTEC HYBRID and the Atego BlueTec Hybrid truck now represent a further step towards the future of the diesel engine.
BlueTec for commercial vehicles and BlueTEC for passenger cars
The introduction of BlueTEC in the passenger car in 2006 marks the beginning of a new era in Mercedes-Benz diesel-powered cars. The engineers of the Stuttgart-based brand initially developed this visionary emission control system for commercial vehicles, introducing it to the market in 2005. BlueTec (it is spelled differently if referring to cars or commercial vehicles) immediately set standards for the reduction of the pollutants in diesel exhaust gas, which promptly was reflected in success on the market: in February 2006 the 10,000th BlueTec truck with Euro 5 engine was delivered to a customer. And in 2008 more than 160,000 vehicles with BlueTec were in operation – with a great many more to come. This is a good foundation for developing BlueTEC for diesel passenger cars.
Evolution of the compression-ignition engine in the car
Considering the history of innovation of the diesel passenger car at Mercedes-Benz, the step to incorporate BlueTEC into present-day cars is only logical: the Stuttgart brand built the first diesel passenger car in 1936. 1971 saw the one-millionth car with compression-ignition engine since the Second World War roll off the assembly line. And in 1976 the C 111-II with diesel engine set standards on its record-breaking run in Nardò. The history of diesel technology is punctuated again and again by such major innovations – especially owing to the initiatives of Mercedes-Benz. Since about 1990 the pace of technological development has picked up very strongly. And this is why in 2006 BlueTEC became the latest standard of this diesel evolution.
Where the development of the compression-ignition engine into a clean and powerful drive for future automobiles can take us is shown by studies like the S-Class S 320 BlueTEC Hybrid, presented at the Frankfurt International Motor Show in 2005, which combines the low-emission diesel with an electric motor. With an electric motor integrated in the powertrain, the concept car was a “mild hybrid,” with significantly reduced fuel consumption especially in inner-city stop-and-go traffic. The diesel engine switches itself off whenever it is not required. All the modifications and features combined reduce the fuel consumption of the BlueTEC HYBRID by some 20 percent versus the comparable predecessor model. The combined output of this S-Class car is 179 kW (243 hp); the combined torque is as high as 575 Nm (424 lb-ft). The car accelerates from standstill to 100 km/h in 7.2 seconds, and its top sped is electronically limited to 250 km/h (155 mph). Fuel consumption (New European Driving Cycle) is as low as 7.7 litres per 100 kilometres. The study made this very clear: at Mercedes-Benz the diesel has great potential as a high-tech drive of the future. And this future already was within close reach, for a few years later BlueTEC HYBRID cars were being built in series.
But for the first, in 2006 the clean Mercedes-Benz BlueTec commercial vehicles were the trendsetters for the car sector, as the highly innovative system for reducing nitrogen oxides (NOX) and other emissions also lends itself to application in passenger cars: BlueTEC reduces nitrogen oxides to such an extent that the toughest emission limits worldwide can be met.
In early 2006 Mercedes-Benz then presented BlueTEC for passenger cars as a ready-for-production package consisting of several components. The extensive optimisation of the engines and the combustion processes taking place inside them constitutes the basis of this package. With solutions like multi-hole injection nozzles, the use of the latest generation of CDI technology and other measures, the raw emissions are cut to an extremely low level. This is where the emission control system with an oxidising catalytic converter (for hydrocarbons and carbon monoxide) and a particulate filter comes in. The final stage is nitrogen oxide reduction by the BlueTEC component proper.
2006 – E 320 BlueTEC, the future of the diesel car
It’s the world’s cleanest diesel: in late 2006 the E 320 BlueTEC hit the US market as the first production BlueTEC car. The E 320 BlueTEC is an innovative model which is based on the sophisticated E 320 CDI V6 and relies on the BlueTEC technology developed by Mercedes-Benz. BlueTEC is the designation for a highly efficient method of minimizing nitrogen oxide emissions already used in commercial vehicles. In contrast to commercial vehicles, the E 320 CDI BlueTEC does not make use of AdBlue® injection but reduces nitrogen oxides with a system based on an improved storage-type catalytic converter.
Three E 320 BlueTEC vehicles also took part in the 13,600 kilometre “E-Class Experience Paris – Beijing” from October to November 2006. This long-distance trip involving a total of 36 Mercedes-Benz E-Class Saloons recalled an adventurous long-distance journey organised in 1907, but which went in the opposite direction, from Beijing to Paris. Despite this major event in the important automotive market China, the E 320 BlueTEC was first put on the market in the United States.
The question may occur why the E 320 BlueTEC made its debut in the USA. One reason, of course, is the growing demand for economical and at the same time clean cars in that country, caused by rising fuel prices. But there’s yet another reason for this specific timing: “The introduction of clean diesel fuel in the USA is something we have been fighting for alongside others for a long time, and an opportunity we wish to use from Day One,” said Dr Thomas Weber, member of the Board of Management of Daimler AG responsible for Research, when the car was introduced in Las Vegas, Nevada.
Modern diesel-engined cars which, in West Europe, account for more than half of new registrations annually, were unable to develop their full potential in the USA due to the excessively high sulphur content in the fuel until then. This changed at the end of 2006 thanks to the nation-wide introduction of clean diesel fuel with a sulphur content of just 15 ppm (15 cubic centimetres of pollutant per cubic metre of fuel). The so-called Ultra Low Sulfur Diesel (ULSD) would be available at up to 76,000 filling stations in the USA in a first step and thereby permit the use of BlueTEC. With this innovative diesel technology, Mercedes-Benz is also able to remain below the strictest globally applicable limits where nitrogen oxide emissions are concerned. Hence, all the preconditions for the breakthrough of modern diesel technology in the USA are fulfilled.
Encouraged by the success of the E 320 BlueTEC developed for the North American market, Mercedes-Benz decided to present the E 300 BlueTEC of the 211 series as first passenger car with BlueTEC for the European market at the end of the year 2007. It easily is the cleanest diesel in its class and fully meets the requirements of the Euro 5 exhaust emission standards.
2007 – BlueTEC in studies and concept cars
Mercedes-Benz demonstrated the direction in which developments in the passenger car sector are going with concept vehicles in 2006, first and foremost the Vision GL 320 BlueTEC and the Vision CLS 320 BlueTEC. The GL has an SCR catalytic converter with AdBlue injection; the CLS, like the E-Class, features an improved nitrogen-oxide storage-type catalytic converter.
The Vision GL 420 BlueTEC presented in 2007 then demonstrated that great fuel economy and extremely low emissions can be achieved with BlueTEC – also, and in particular, in large and powerful cars. The high-performance V8 diesel engine develops 216 kW (290 hp), has a torque of 700 Nm (516 lb-ft) and is expected to have a fuel consumption of just 9.8 litres per 100 kilometres. The car’s independent styling expresses the special status of the GL 420 BlueTEC and at the same time meets the wishes of Mercedes-Benz customers in the USA for even greater exclusiveness and individualisation. The redesigned, distinctively swept-back front end with its dominant radiator grille expresses the extraordinary performance of the V8 diesel engine in the car’s appearance and gives the car a dynamic forward thrust even when it’s stationary. These self-assured looks are enhanced by flared wheel arches, representative 21-inch wheels and lateral floorboards.