The new Mercedes-Benz C 350 e offers all the appeal of a Mercedes C-Class together with an official combined fuel economy figure of 134.5mpg, emissions of 49g/km CO2 and Benefit in Kind of just 7% – surely this must be an attractive company car proposition?
Diesel has been the most popular engine choice for cars such as the Mercedes C-Class in the UK over recent years since the government started to encourage low CO2 cars. However the tide is now turning; the issue of local air quality is rising up the political agenda and now petrol plug-in hybrids, encouraged by low Benefit in Kind company car tax rates, are the flavour of the month.
Mercedes fans can relax, as the C 350 e is still a C-Class at heart, just with a plug-in petrol-electric hybrid powertrain. So the C 350 e has the latest curvy exterior design language, and modern interior. Many people seem to prefer the interior, with lots of shiny black plastic and chrome effect, to that of rivals.
Our test car was an Estate. The latest C-Class Estate isn’t the largest load-lugger around anyway, and thanks to the battery, the plug-in hybrid model has a higher boot floor, so further encroaching on space.
Under the bonnet there’s a two-litre 211hp/350Nm petrol engine, mated with a 6.2 kWh lithium-ion battery and 82hp/340Nm electric motor, giving a total system power output of 279hp and 600Nm of torque. A 7G-Tronic Plus 7-speed automatic transmission transmits drive to the rear wheels.
The secret behind the 134.5mpg figure is that the C 350 e is a plug-in hybrid, meaning that you can plug it in to the mains and give the battery a charge that will provide an official range of 19 miles. However one of the downsides of two powertrains is an inflated kerb weight of 1840kg.
The charging socket for the C 350 e is found in the corner of the rear bumper on the driver’s side, a location which seems potentially vulnerable to collision damage.
The whole point of the C 350 e is that you drive it on electric power as much as possible, and when you do, like most electric cars, it’s quiet, smooth and refined. At the other end of the scale, the C 350 e is also at home on the motorway when running on its petrol engine, when it feels stable and comfortable.
The C 350 e is also good to drive on A and B-roads, as long as you don’t ask too much of the car, or in particular the transmission. The steering feels responsive and body control is good, which was helped by the Airmatic suspension on our test car. Of course the C 350 e is rear-wheel drive which provides a more rewarding handling experience. Even the brake feel is decent, something that can’t always be said for hybrid cars.
Once off the mark the C 350 e has good acceleration. However after engaging Drive or Reverse it can be slow to respond to throttle input from standstill.
The hybrid system mostly works well, but you can sometimes feel the changeover from electric to petrol. However the main issue is that during deceleration and braking a jerky sensation can be experienced.
You can choose between Hybrid, Charge, e-Save and e-Mode. There’s a button to change these hybrid settings but you can’t see this button from the driver’s seat (on right-hand drive models) as it’s hidden behind the infomedia controller. There are also Eco, Comfort, Sport, Sport Plus and Individual drive modes. Eco mode really dials back the throttle response.
We still find that it’s too much having four stalks on the left hand side of the steering column (indicators/wipers, cruise control, gear paddles and steering column adjustment). It’s all too easy to reach for the indicator, but to mess up the cruise control/speed limiter instead. For people who drive a range of cars, it’s also possible to knock the car out of gear by pushing the right hand (gear selector) stalk out of habit, thinking that it’s the windscreen wiper stalk. This layout of controls won’t be a problem for regular Mercedes drivers, but it might be a challenge for people switching to the brand for the first time.
To see the battery charge you can scroll through the read-outs in the instrument cluster but it would be better if this information was visible all the time.
One good point about the C-Class is that there’s a controller for the infomedia system that sits between the front seats, so avoiding the problems of having to try and press the right button on touchscreens when driving at speed.
The official combined NEDC economy figure for the C 350 e is 134.5mpg. This sounds crazy, and it is – unless you drive on electric power for the vast majority of the time. Our time with the car was a typical week up and down the nation’s motorways, so only a small proportion of driving was carried out on electric power. The result was an average of 38.1mpg. This is one of the better outcomes for a plug-in hybrid under such driving conditions, helped by the fact that the C-Class is more aerodynamic than many other plug-in hybrids.
The C 350 e has an official range on its battery of 19 miles – which isn’t a lot. In real-life driving this was typically around 12-14 miles. So both economy and range are likely to be less than expected.
A full recharge of the battery typically takes up to two hours, but this depends on the charging equipment and electricity supply.
The C 350 e Sport Estate costs £39,470 – or in the case of our test car, including options, £46,885. This is getting somewhat expensive for a car that won’t be as economical as a diesel for many people.
You can also have a Saloon as a plug-in hybrid. And apart from the plug-in hybrid powertrain, you can choose from a wide range of petrol and diesel C-Class models.
The C 350 e is only available in Sport trim. This means plenty of equipment such as leather, navigation and parking assistance systems. It also includes Mercedes’ Airmatic air suspension as standard, presumably to help compensate for the extra weight of the C 350 e over a standard four-cylinder petrol model.
All the basics are there in the C 350 e. Essentially it’s a good car to drive, being refined, comfortable and (mostly) responsive, the interior will appeal to many, and a certain cross-section of people will aspire to the Mercedes badge. However it’s let down by a few details, such as the slow response from standstill, and the occasionally jerky powertrain when braking/decelerating.
For potential buyers of the C 350 e, if their driving cycle means they’re typically only driving the car around 20 miles between charges, with occasional longer journeys, the C 350 e makes sense. Our concern is that a new Mercedes C-Class is usually bought by company car drivers who typically drive a lot more than 20 miles between charges. In which case a diesel would be better for them, however the BIK system will encourage them to buy a plug-in hybrid. If they don’t pay for fuel personally then the company is likely to end up footing the bill for a 40mpg C-Class, when a 50-60mpg diesel C-Class would be a better buy.
So the Mercedes-Benz C 350 e Sport Estate is essentially a decent car and is awarded a Green Car Guide rating of 8 out of 10. However the UK’s company car tax system needs to be reviewed to ensure that plug-in petrol hybrids with official figures of 134.5mpg and 49g/km CO2 aren’t bought and used in situations where the real-life economy and emissions will be much worse.