First shot in luxury green war

Mercedes-Benz S Class. Photo / Supplied

Mercedes-Benz is to roll out an S-Class sedan with a four-cylinder diesel engine, the first of the German luxury carmakers to do so to help meet new fleet exhaust emissions standards in Europe.

The new S-Class is the first in the flagship model's 60-year history to use a four-cylinder unit. It arrives as Mercedes-Benz tussles with BMW and Audi for "green" bragging rights.

BMW has invested €1.2 billion ($2.1 billion) in fuel-saving technology, while Mercedes-Benz has nearly doubled its investment on "green" development to €1 billion this year.

Mercedes-Benz aims to maintain S-Class performance even with a downsized engine. The S250 CDI, which will arrive at European dealers early next year, combines mild hybrid technology with a 2.2-litre twin-turbocharged diesel that delivers 155kW of power and 500Nm of torque from 1600rpm.

The S250 CDI uses stop-start technology for a claimed town-and-around fuel consumption of 5.7 litres/100km (50mpg) and CO2 emissions of 149g a kilometre.

Mercedes-Benz claims it is the first car in the top-end luxury segment to run on under 6 litres/100km and the first vehicle in its class to attain CO2 emissions below the 150-gram mark.

The two-tonne sedan has a top speed of 240km/h and sprints from zero to 100km/h in 8.2 seconds.

Coby Duggan, general manager of Mercedes-Benz passenger cars in New Zealand, said the new model's statistics were impressive. "But we don't have a plan to bring the car into New Zealand in the short-term.

"We will work with our colleagues at Mercedes-Benz in Australia to see what they might have in mind. But for now the entry-level S-Class models for New Zealand will remain the V6 petrol and diesel offerings."

Such engine downsizing is also a reaction to the financial crisis, which sapped demand for luxury cars worldwide.

"Green luxury is feasible," said Verena Mueller, a Mercedes-Benz spokeswoman in Germany. "We expect to attract environmentally conscious customers who are seeking the lowest possible CO2 emissions.

Besides private customers, that could of course also be fleet buyers."

Smaller engines are cheaper, so offer a financial incentive to keep customers from trading down to less expensive model lines.

"We're going to start seeing extreme versions of bigger cars to keep customers from drifting down" to smaller models, said Christoph Stuermer, a Frankfurt-based analyst at IHS Automotive. But BMW isn't planning to follow Mercedes-Benz by rolling out a four-cylinder version of its flagship line. It is building a hybrid supercar and an electric model for city driving.

"I like selling 7-Series cars with six and eight cylinders," said BMW chief executive Norbert Reithofer. "What we need to offer with these cars in the future is electrification."

BMW is developing a production version of the Vision Efficient Dynamics concept car for sale in 2013.

The four-seater sportscar combines a three-cylinder combustion engine with two electric motors and can sprint from zero to 100km/h in a claimed 4.8 seconds. BMW claims CO2 emissions of 99g/km.

Audi is following a similar approach and plans to couple smaller engines with electric motors. The carmaker is developing a version of the A8 that will combine a four-cylinder petrol engine with an electric motor.

Audi spokesman Eric Felber said the hybrid sedan was slated for 2012.