In seven decades, the power and torque of diesel engines have been dramatically improved.
Even more impressive, of course, is the fuel economy of modern diesels. Whereas the world’s first diesel passenger car consumed 0.4 pints of fuel per 100 kilometres to generate one hp, today’s C 320 CDI uses only 0.05 pints per hp for the same distance - an extraordinary 90 per cent reduction in fuel consumption. Or, in other words, the engine uses one tenth of the fuel required by the first diesel. In addition to conserving resources, of course, this development is also more environmentally compatible.
While the power-to-swept-volume ratio of diesel passenger cars is increasing, their fuel consumption is dropping significantly.
A diesel particulate filter that’s well-suited for everyday use
At the same time that fuel efficiency was increased, emissions were radically cut. Introduced in the C- and E-Classes in October 2003, the world’s first additive-free particulate filters already reduced emissions below the levels proscribed by the stringent EU emissions limits that have also been in force for diesel vehicles since January of this year. These limits stipulate that emissions be reduced by more than 81 per cent (carbon monoxide) compared to 1995. In addition, particulate emissions have to be reduced by more than 80 per cent over the same time period.
Thanks to the particulate filter, Mercedes Benz diesel passenger cars satisfy the most stringent emissions limits of the Euro 4 standard.
Mercedes Benz achieved these reductions by combining EU-4 compliance technology with a diesel particulate filter that works reliably without needing fuel additives. What’s more, this filter achieves an excellent operating performance and low fuel consumption without requiring any additional servicing measures, making it eminently suitable for everyday use. Although the filter must be eventually regenerated, this is achieved by adjusting, in accordance with requirements, various engine-control functions, such as fuel injection, intake-air throttle, exhaust-gas recirculation and boost-pressure control. Test results show that, after high mileage, the residual ash in the filter is up to 75 per cent less than that produced by additive-dependent filter systems. Sulphur-free fuels and specially developed engine oils will mean these diesel particulate filters can have an even longer service life.
Mercedes Benz continues to focus its entire innovative capacity on reducing emissions of particulates and nitrogen oxides to the very limits of what is still measurable - utilising CDI technology and future homogeneous diesel combustion processes. In doing so, the brand that originally adapted diesel engines for use in passenger cars has given a clear signal in support of the diesel engine, which still has a great future ahead of it, according to the experts.