Bosch has revealed that in January this year, Bosch passed the 50m milestone for the production of common-rail systems produced for diesel engines.

Series production for this technology started in 1997.

"In conjunction with turbo-charging, the common-rail injection system paved the way to the break through of the diesel engine," said Dr Ulrich Dohle, President of the Bosch Diesel Systems division.

"Since the introduction of emissions legislation in 1990, we have also been able to reduce fuel consumption by 30 percent and pollutant emissions by more than 95 percent¨.

The term 'common-rail' describes a high-pressure accumulator, or rail, from which the fuel is injected into the cylinders via the injectors connected to it. The first customers, Alfa Romeo with the 156 JTD and Mercedes-Benz with the 220 CDI, began marketing models featuring Bosch common-rail systems at the end of 1997.

By 2001, three million Bosch common-rail systems were in use, and by 2002 the figure had already risen to 10m systems. The proportion of diesel cars in Western Europe increased from 20 to over 50 percent between 1997 and 2007.