This is eerie. I’ve just climbed into a Mercedes-Benz E-Class and started the engine. It’s quiet. Really quiet. I know an executive saloon has to be properly sound-proofed but this is something different. As I pull out of the car park and head out onto the main road the spooky silence continues.

Mercedes-Benz E300 Bluetec Hybrid

Mercedes-Benz E300 Bluetec Hybrid

Of course, this is no ordinary E-Class. This is the new BlueTec Hybrid model that combines a 201hp 2.1-litre twin-turbo diesel with a 27hp electric motor. One of its party tricks is the ability to travel short distances on battery power alone and that’s exactly what it’s doing. If you’re gentle with the throttle you can squeeze as much as 0.6 miles in electric mode.

Eventually the battery power runs out and the diesel engine starts itself up with a quiet rumble. Now it feels like a normal E-Class, wafting along with ease as the 7-speed automatic gearbox shuffles up and down its ratios.

All of the energy for the electric motor is generated when the car is on the move, charging up when you’re driving on a trailing throttle or under braking. You can feel it when you lift off and the car slows more quickly than you would normally expect, with the increased braking effect driving energy back into the lithium-ion batteries.

Mercedes-Benz E300 Bluetec Hybrid

Mercedes-Benz E300 Bluetec Hybrid

This system isn’t designed to power the E-Class for long distances and neither will it give a huge surge in performance. What it does do is cut the amount of time the engine has to be running in normal driving. As you pull up at a junction or roundabout the engine will switch off and, if there’s enough energy stored up in the battery, you can pull away again using just the electric motor.

The results are impressive. The non-hybrid E250 shares the same diesel engine and returns official figures of 47.1mpg and 136 g/km of CO2. The electric motor in the E300 Hybrid stretches a gallon of diesel out to 68.9 miles and cuts CO2 to 109 g/km. Even if you don’t see economy figures as good as that in normal driving the CO2 reduction drops the E300 into VED band B and cuts the BIK of company car drivers from 21% down to 13%.

The various hybrid components, including the motor and battery, push the E-Class’s weight up by 70kg to a total of 1840kg. They’re all located in the engine bay so there are no worries about losing space in the cabin or boot, so it’s business as normal for passengers.

Despite the extra complexity in the engine compartment the E300 Hybrid drives the rear-wheels just like any other E-Class. While there is enough power to propel the E300 to 62mph in 7.5 seconds you’re not going to be enjoying the same sort of tail-happy antics as you could in the bigger engined models, but if that’s what you’re really after then you’ll barely give the BlueTec Hybrid a second glance.

Mercedes-Benz E300 Bluetec Hybrid

Mercedes-Benz E300 Bluetec Hybrid

What this E300 does do is Comfort with a capital ‘C’. The suspension is on the soft side, very much like the leather seats, but that just serves to eliminate distracting bumps and crashes from the road. This is a place where you can relax and watch the world go by in a well-equipped and nicely detailed cabin. Automatic climate is standard, as is Bluetooth and multimedia connections. There are also Active Park Assist and Collision Prevention Assist systems to look after you, while adaptive cruise is one of the many options.

Hybrids aren’t a typically Driving Spirit kind-of-car and I’m not going to go anywhere near the arguments about their place in the future of motoring. The E300’s emphasis on comfort and refinement don’t quite tickle my fancy but I have to say I like the E300 BlueTec Hybrid because it really is an impressive piece of engineering. It significantly boosts the economy of the diesel engine while sacrificing nothing in the driving experience, other than adding short periods of serene progress.

Mercedes-Benz E300 Bluetec Hybrid

Mercedes-Benz E300 Bluetec Hybrid

Some will criticise the E300’s lack of battery range and say that it’s not a proper hybrid. However, unlike certain other hybrids that use petrol motors and can often be found running flat out in the fast lane of the motorway where their hybrid technology is of little use, the E300 can run for hundreds of miles sipping away at its diesel tank. The E300 might not have the same green credentials but in that sort of environment it’s a lot more efficient.

You might need to do a few sums to decide if it’s worth paying the extra £5,435 over the E250 CDI but if the maths do work out you should have no qualms about choosing the Bluetec Hybrid. Once you’re behind the wheel you’ll realise just how much of a non-event this hybrid technology is – and that’s to the credit of Mercedes’ engineers.

Mercedes-Benz E300 Bluetec Hybrid Specifications

Engine: 2,143cc 4-cylinder turbo diesel / electric motor
Power: 201 bhp / 27 bhp
Torque: 369 lb/ft / 184 lb ft
0-62 mph: 7.5 seconds
Top Speed: 150 mph
CO2 Emissions: 109 g/km (Band B)
Official Economy: 68.9 mpg
Insurance Group: 34
Price (OTR): £39,475*

*Prices taken from Mercedes-Benz website, February 2013