Mercedes-Benz C350e: the plug-in C-Class

The proliferation in plug-in hybrids continues unabated with the introduction of this remarkably frugal petrol-electric powered version of the classy new fourth-generation Mercedes-Benz C-Class – the C350e as it is called.

To be sold in Australia in sedan and wagon bodystyles from the second half of 2015, the C350e is the second of up to 10 plug-in hybrid models Mercedes-Benz plans to launch by the end of 2017 as part of a multi-million dollar technical initiative by the German car maker, following on from the larger S500 Plug-In Hybrid which we first drove late in 2014.  

First among many

At the moment, it goes without any direct competition in its class. But with key rival BMW planning to reveal a plug-in hybrid as part of a facelifted 3-Series line-up later in 2015 and Audi hard at work on a similarly conceived version of the all-new A4 due for introduction in 2016, the new C350e will not be alone in offering buyers limited all-electric running capability at the more affordable end of the luxury car segment.

First revealed at the Detroit motor show back in January, the rear-wheel drive Mercedes-Benz relies on a combination of a turbocharged 2.0-litre four-cylinder petrol engine and an electric motor mounted within the front section of its standard seven-speed automatic gearbox for propulsion.

The combustion engine garners 155kW and 350Nm, as in the C250. The disc shaped electric motor, which is capable of powering the C350e on its own for worthwhile distances, is rated at 60kW and 340Nm. Altogether, the new plug-in hybrid system offers a combined 205kW and 600Nm, making this latest C-Class model the most powerful save for the turbocharged 3.0-litre V6 petrol powered C400, which musters 245kW and 480Nm.

They are sufficiently strong reserves, according to Mercedes-Benz's figures, to provide the C350e with a highly respectable 0-100km/h time of 5.9sec and a top speed limited to 250km/h. All, while providing remarkable combined fuel consumption of 2.1-litres per 100km and average CO2 emissions of just 49g/km.

Electric Avenue

Its main attraction, though, is its ability to run on electric power alone for a useful 31km at speeds up to 130km/h when its 6.38kWh lithium ion battery is fully charged – a process which is claimed to take 1 hour 30 minutes using an optional high voltage wall box or around 2 hours on a regular mains connection.      

An impressive set of figures, then. But does the driving experience do them any justice?

Driving the C350e can be an overly complex affair, but only if you choose.


In Mercedes-Benz's attempts to offer as broad a range of driving characteristics as possible, the driver is given far too many different combinations; it's a car seemingly built more for technology obsessed engineers keen on eking out the very last smidgen of efficiency from its petrol-electric system than your average luxury car driver.

Indeed, there are no less than five different driving modes - economy, comfort, sport, sport+ and individual. On top of this, it also possesses four operating settings for the hybrid driveline – hybrid, e-mode, e-save and charge.

Simple or complex - you choose

As interesting as it is to flick through the varying modes and witness a dazzling assortment of associated graphics within the free standing infotainment monitor, you quickly come to the realisation that the most efficient and accommodating way of operating the C350e over any given journey is simply to stick it in economy and leave it .

Here, you can drive it on electric power alone when there is sufficient battery charge, making use of one of the new car's more handy features, the so-called haptic accelerator pedal. It allows you to operate on the electric motor alone up to a certain point of resistance, but push beyond it and the petrol engine fires for added performance.

The C350e is at its most impressive in an urban running at low-to-moderate speeds on electric power. The inherent qualities of the electric motor combine to make it terrifically smooth, responsive and refined. In this sort of driving environment, it exudes a truly premium feel.

Spoiler alert

Unfortunately, the premium impressions are removed the moment the petrol engine kicks in, be it because the electrical energy store of the battery has run low or you have called up extra urge with an added nudge of the hi-tech accelerator pedal. The four-cylinder unit is surprisingly vocal and lacks for smoothness in the crucial start up phase, spoiling the new car's otherwise silent running characteristics and superb refinement.

At 1780kg in sedan guise, the C350e weighs a considerable 375kg more than the C250, so you can forget about muscle car levels of performance. But with that solid slab of torque and some well chosen gearing, it possesses urgent step off qualities and brisk in-gear acceleration up to posted limits.

The plug-in component of the C350e is handled by a plug set in the right hand side of the rear bumper and a sturdy lead that is used to connect to the electricity supply. It is simple enough to operate, although the cubby hole used to stow the lead in the side of the boot is quite a flimsy affair and shares the limited space with the first aid kit, making it difficult to access. Given most owners will be looking to charge their car at least once a day, you'd have thought that Mercedes-Benz may have come up with a classier stowage idea. Shame.

The packaging of the battery at the rear has raised for floor of the boot by 50mm, reducing luggage capacity in the sedan from 480 litres to a hatchback like 335 litres.

Likely loaded

While details to Australian versions are yet to be made public, European versions of the C350e come loaded with plenty of standard equipment, including leather upholstery, various parking assistance, a navigation system and 18-inch alloy wheels.

Somewhat at odds with its billing as a economy champion, the standard equipment also includes Mercedes-Benz's Airmatic air suspension, which makes for a lovely controlled ride, particularly at city speeds, while lessening the impact of the added 375kg in kerb weight on the handling, providing the C350e greater resistance to lean in corners and a self levelling feature when it is loaded up with passengers.

The C350e exempifies contemporary motoring with a driveline that is both powerful and thanks to its use of stored electricity as a primary source of propulsion incredibly economical in prevailing consumption tests. In city driving it is superbly smooth and refined, but on more open roads its petrol engine proves harsh and rather noisy as it kicks in.