Mercedes S-Class hybrid looms closer

Lexus is currently the only manufacturer to offer hybrid powertrains in the premium end of the market (LS 600h, GS 450h and RX 400h), but Mercedes-Benz is about to get into the act, and further proof will come at September's Frankfurt motor show, according to Euro sources.

The three-pointed star will use the Frankfurt expo to take the wraps off a near production-ready variant of the S-Class Bluetec Hybrid, which mates a combustion engine (claimed to be the "cleanest diesel in the world") with a supplementary electric motor.

What's with the 'Bluetec' moniker? Well, that's basically the Benz marketeers' way of getting around the negative perceptions of diesel in the potentially lucrative US market. So, instead of diesel or CDI badges, they've whacked a 'Bluetec' label on its rump (more here).

As per its hybrid counterparts over at Lexus, the S-Class cuts the combustion engine when it's not required and it makes use of regenerative braking (using braking energy to generate electric charge) to maximise efficiency.

Mercedes claims the hybrid system delivers fuel savings of around 20 per cent compared with a regular diesel equivalent.

Interestingly, Mercedes hasn't opted for a particularly potent powertrain as the diesel engine in question is reportedly a 2.2-litre Bluetec unit. Working in tandem with the electric motor, it adds up to a combined output of around 180kW, but the real kicker is a peak torque figure of about 540Nm.

Word has it the large Benz sedan will be capable of knocking off the 0-100km/h dash in about seven seconds, which may not be electrifying, but it's hardly on the sluggardly end of the scale either.

And its greenie credentials are boosted by a process called "Selective Catalytic Reduction" that injects urea (er, basically pee) into the exhaust to nullify toxic gases and reduce nitrogen oxide emissions by 80 per cent.

Mercedes has exhibited diesel hybrids at previous motor shows, including the 2005 Detroit show, where it showcased the S400 Hybrid, powered by a V8 CDI diesel engine and two electric motors. The electric motors were powered by a 1.9 kWh nickel-metal hydride battery housed in the boot.

Expect Mercedes-Benz to debut its diesel-hybrid technology in the international market by 2008.

To comment on this article click