Serck, the specialist in heat exchange technology based in Birmingham, continues its world lead in the development of low-emission diesel engines with the announcement that BMW will fit its cooling system to the 3 Series diesel-powered saloon cars due for launch in the UK in September.
The technology is based on a refinement of the principle of exhaust gas recirculation (EGR), which extracts the maximum fuel benefit before dumping the remaining unburnt hydrocarbons as well as nitrous oxides into the atmosphere.
Serck’s exhaust gas cooling system (EGC) improves on EGR, further reducing the levels of Nox released into the atmosphere by around one third. Hydrocarbon emissions are cut proportionately.
The EGC system works by cooling the gas to reduce its volume, thereby increasing the mass of exhaust gas available for re-burn. The lower combustion temperatures lead to lower Nox levels.
Vehicles already fitted with EGC are the 2.5 litre direct injection diesel engine on Ford Transits launched in 1994 and, most recently, the Land Rover Freelander, which is fitted with a 2-litre 97Ps L Series direct injection turbo-diesel engine.
A number of companies are working on EGC technology but their developments have yet to make it into production vehicles.
Serck says EGC is not a replacement for intercooling systems which are most effective at high engine speeds. EGC complements such systems at the middle and lower power bands.