The Mercedes-Benz E300 Bluetec Hybrid is a rather intriguing proposition for executive buyers with an environmental bent, given it combines a diesel engine with a hybrid drivetrain to yield rather remarkable claimed fuel consumption.
Rivals Lexus and BMW both offer petrol-hybrid vehicles, granted, but neither of the two achieves the incredible claimed fuel consumption figures Mercedes-Benz boasts with the E300 Bluetec Hybrid, or match its boot space. It's a small corner of the market in terms of sales volume, but bragging rights are important on cars like this.
Built on the five-year-old W212 platform, the E300 Bluetec Hybrid uses the $10,000 cheaper E250 CDI as its donor car. So there's a sizeable premium for the extra green-tinged tech. Hybrid components are integrated into the existing chassis to create a car that looks identical to the naked eye.
Stylistically, Mercedes-Benz’s trademark grille features an oversized Mercedes-Benz badge and chrome highlights to differentiate it from other vehicles in the range. At the rear, LED taillights help give the E-Class a more premium feel.
An interesting tidbit for trainspotters is that the Mercedes-Benz logo on the grille of vehicles with radar cruise control is flat and glossy, while vehicles without this radar module feature a more traditional exposed and embossed Mercedes-Benz logo.
Inside the cabin, the E300 Bluetec Hybrid feels a bit dated. The W212 launched in 2009 and aside from a recent exterior facelift, the interior remains largely unchanged. The central COMAND system controls audio, navigation and the car’s applications. It’s clumsy and lacks refinement in comparison to BMW’s iDrive and Audi’s MMI.
There is plenty of room to seat four adults comfortably with easy entry and egress thanks to wide opening doors. The roofline offers enough room for tall passengers sitting in the second row.
Remarkably, the boot offers 540-litres of capacity, even with the hybrid components hidden on board. In comparison to the BMW ActiveHybrid 5 and Lexus GS450h, that’s an additional 165-litres and 75-litres respectively.
Behind the wheel, the E300 Bluetec Hybrid initially feels no different to the E250 CDI. From a standing start, the vehicle moves off on battery power before the diesel engine switches on. The LCD display in the instrument cluster shows battery charge levels, along with the direction of energy flow.
The E300 Bluetec Hybrid thankfully retains its handling dynamics, despite carrying an additional 70kg of batteries and an electric motor. The electric steering is fairly direct and offers adequate communication and resistance at speed for sporty driving. At low speeds it remains light and easy to use, which helps with parking and low-speed manoeuvres.
One benefactor of hybrid technology – aside from fuel efficiency – is acceleration. Without hybrid running gear, the E250 CDI donor car produces 150kW of power and 500Nm of torque from its 2.1-litre four-cylinder turbocharged diesel engine. Add an electric motor and some batteries and those figures increase to 170kW of power and 590Nm of torque respectively.
Like all electric motors, torque is available from zero rpm, which means acceleration from a standing start is rapid and relentless. The seven speed automatic gearbox offers very smooth gearshifts and intuitive gearing, which is especially handy while driving up and down hills.
Hybrid technology produces the most energy savings when used from a standing start. The energy required to move a large mass (such as a car) is generally greatest when setting off. That’s why the E300 Bluetec Hybrid (and most other hybrids) will take off on battery power and then engage the internal combustion engine to take over.
The best example of this theory would be pulling or pushing the oversized, redundant dressing table your wife just bought on carpet (welcome to my weekend). You need to exert a great deal of energy to initially shift the weight, but once it starts moving it becomes much easier to keep moving. The diesel hybrid drivetrain in the E300 Bluetec Hybrid works on the same principle.
Mercedes-Benz goes one step further and allows the diesel engine to switch off at speeds of up to 160km/h. It’s an eerie feeling to have the engine switch off at highway speeds, only to fire up again when you depress the throttle.
This combination of energy saving technology allows the E300 Bluetec Hybrid to consume just 4.3L/100km on average. In reality, this figure is difficult to achieve due to impatient drivers and the need to keep up with traffic. The car will only run on electric power for a short period before you demand more power to keep up with traffic. You can realistically expect to achieve around 6-7L/100km depending on your driving style.
You should also consider that the E250 uses a claimed 4.9L/100km, only 0.6L more than the E300.
As a piece of engineering, the E300 is an impressive beast. But one could also argue that it’s hard to justify spending an extra $10,000 when the E250 CDI is just as competent and almost as efficient. It’s a case of horses for courses and weighing up exactly what you’re after from a luxury German sedan.
But if a hybrid drivetrain is a must have, the Mercedes-Benz E300 Bluetec is the most affordable and efficient of its type at this end of the market.
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