The Volvo Group's new generation of diesel engines with SCR are optimised to provide the most complete combustion possible. The SCR technology enables the engine to be optimised for lowest possible fuel consumption and the ultralow
particulate levels required by Euro 5.

Once the exhaust gases leave the engine, all that remains to be done is to reduce out their nitrogen oxides. This is done with the help of SCR. It is an effective and thoroughly tested method of cleaning up exhaust gases. It has long been used for stationary power units and has now been developed and modified to suit heavy duty vehicles. In this method, a mixture of urea and deionised water known as AdBlue is sprayed into the exhaust gases. The heat of the
exhaust system transforms the urea into ammonia which reacts with the nitrogen oxides in a catalytic converter, converting them into harmless nitrogen gas and water vapour.