COVER Mercedes C 300 e

response away from the line and just a hum of road noise, but little else.

Brake regeneration is used to put energy back into the battery when slowing down. On its own, the system does this ‘intelligently’ , decelerating more when approaching junctions or if traffic slows ahead. Some will think it’s all very clever, but it makes the car a little hard to predict; we found greater consistency by fixing the regen settings.

If there’s enough charge in the battery, the C 300 e defaults to EV mode. In the hybrid setting, heavier presses of the throttle will bring the combustion engine into play. The 2.0-litre petrol has 201bhp, which means a combined output of 309bhp and 550Nm of torque. The result is a more-thanadequate 0-62mph dash of 6.1 seconds.

The key figure is fuel economy, though. While this will vary drastically depending how you drive and how often you charge, we often saw 60-70mpg. That’s similar to what we achieved with the less powerful C 220 d, which is only £3,200 cheaper.

But the diesel model can’t compare for company car tax rates. With CO2 emissions of just 13g/km, the C 300 e means annual deductions of £1,480 for a higher-rate income tax payer, which contrasts with a bill of £4,989 for C 220 d drivers.

So are there any downsides? It’s a shame that our car had no provision for DC rapid charging. The C 300 e is available in some markets with 55kW charging, which replenishes the battery in around 30 minutes, but UK cars are AC only. You’ll need two hours for a full charge at 11kW.

The other downside is the braking. As with most plug-in hybrid and fully electric vehicles, the first part of the pedal travel works with the motor regen, and heavier stops are aided by the mechanical brakes. The regen part here is very long and very soft, and even with a harder press it’s still not particularly reassuring, although the brakes bring the car to a halt quickly enough.

The need to package the hybrid tech has compromised practicality, too. Due to a raised boot floor, the load capacity drops from the saloon’s 455 litres to 315 litres.

These points aside, the C 300 e is the same C-Class we’ve come to admire. It’s not quite as sharp to drive as a BMW 3 Series, but it’s impressively stable at speed, and its ride is slightly softer than its rival’s.

The brilliant MBUX infotainment is also standard. The 11.9-inch touchscreen looks sharp, is responsive and presents apps such as Apple CarPlay and Android Auto across its entire display. Even the on-screen climate controls are no hardship to use; they’re a permanent fixture, and the keys are large enough to make minor adjustments easily.

The rest of the cabin is impressive, too –more contemporary than a 3 Series, though the BMW has more headroom in the back.

Verdict

THE C 300 e is a champion of efficiency, offering huge potential for low-cost motoring if you use what its powertrain has to offer. With a superb electric-only range and strong performance, many drivers could realistically use this as a full EV much of the time. And on long journeys it benefits from its refined engine, comfort and slick cabin tech.

des C 300 e

Performance

0-62mph/top speed 6.1 seconds/152mph

Running costs

470mpg (official) £83 fill-up

ectric-only range and low CO2 emissions make this plug-in hybrid the ultimate C-Class?