Merc's radical B-class

The all-new Mercedes B-class is set to shake up car industry convention when it is launched late this year thanks to its ability to accommodate up to five different drivetrains in the same basic platform.

As well as a conventional diesel and petrol engines, the Mercedes B-class will also be offered with pure battery power, with hydrogen fuel cell power, natural gas and as a range-extender with both a battery pack and three-cylinder engine/generator.

The gas tanks and battery packs are packaged inside a sandwich floor layout, similar to the one used by the outgoing B-class model. While the new B-class platform is conventional in its front wheel drive layout, for the alternative fuel versions the floors of the rear footwells are raised by around 80mm, creating a sizeable void in which can be fitted smaller gas tanks and battery packs.

The larger tanks used to store hydrogen and natural gas fit under the rear seats in the space used by the conventional fuel tank.

The flexibility of the new Mercedes B-class MPV will give Mercedes the ability to sell the car globally, but equipped with alternative drivetrains that suit local market conditions. Natural gas, for example, is becoming increasingly popular in European city centres that are banning diesel-powered vehicles such as taxis.

Mercedes-Benz-B-Classphoto : autocar.co.uk

The conventionally-engined B-class models gain all-new petrol and diesel engines as well as a new 7-speed dual-clutch transmission. The 1.6-litre turbocharged petrol motors offer 120bhp and 154bhp and a remarkable, diesel-like, torque curve which sees the twist action hit its peak at just 1250rpm.

Both engines are claimed to offer ‘significant’ improvements in fuel economy over both the ‘slant’ engines in the current B-class and the 1.8-litre engines used in current C- and E-class models. Indeed, the newly-engineered M270 petrol engine and OM657 diesel will soon find their way into the bigger cars.

The B-class’s styling and detailing has been very finely tuned for maximum aerodynamic advantage. The standard model has a Cd figure of just 0.26, much better than rivals such as the Golf Plus and Ford C-Max, but a future ‘eco pack’ version will manage a rating of just 0.24.

The B-Class will be unveiled at the Frankfurt show in September and is expected in the showrooms by December. Its Golf-rivalling A-class sister car (which doesn’t get the option of the alternative drivetrains) arrives later. Both cars are said to be notable for their high quality interiors and switchgear, some of which is shared with executive models.

Mercedes is also packing its new cars with safety technology from further up the range, including anti-collision brake assist which works from 30kmh to the car’s maximum speed.

Four wheel drive will be an option (partly thanks to the new four-link independent rear suspension) and an AMG version of the A-class is expected during 2012. Further out, a three-door ‘coupe’ A-class is planned and there are rumours of a B-class-based off-roader.

Hilton Holloway
Autocar