Plugging the gap

Here’s a clever, sophisticated and practical car that ticks every box for executive chauffeuring. Comfortable and bristling with safety technology. It has low CO2 emissions thanks to diesel rather than petrol powering the internal combustion component of the hybrid powertrain. Diesel also means a decent range even without plugging in, yet if you do top up the battery, it’s capable of enough zero-emissions mileage to satisfy TfL’s licensing wonks.

Yet the Mercedes-Benz E300de feels like the end of something rather than the obvious choice. With electric cars gaining traction in the car market, what’s the future for the plug-in hybrid? PHEVs even lose their Congestion Charge exemption from October 2021, so even though you can licence a new one, it gains no special treatment any more in London.

But for now, what’s the alternative? BMW’s 530e is in the same boat. Tesla is the obvious executive EV, but the Model S is not available at the moment, and in any case, it’s priced more like an S-Class than an E-Class. The Model 3 is available, but for all its futuristic feel, it’s a long way short of executive luxury. There are several electric SUVs, but not everyone wants to ride in one – they just don’t have the same prestige as a saloon.

So for now, if you’re looking for a replacement for that ageing diesel E220d or E250d, here’s the best option for the time being. And make no mistake, it’s a very good car – with one or two obvious failings.

Mercedes-Benz considers the E-Class to be at the heart of its range, and is continuing to refine it in parallel to its EQ electric vehicle programme. The current 10th-generation E-Class was launched in 2016, and this final facelift will carry the E-Class into the EV age – an EQE is due to break cover some time next year, and this all-electric model will surely become the standard.

Externally, it’s not easy to spot the revisions on the E300de. The styling has a more sporty touch, with the front sections in particular being given a fresh look. The all-LED headlamps have been given flatter housings, while the LED tail lights have been reworked too.

The big revisions are under the skin. What’s new under the bonnet applies mainly to the pure petrol and diesel models, where integrated startergenerators add a degree of mild hybridisation. And there’s a new petrol engine with 48-volt electrics – a signpost to the future for all ICE Mercs.

But these vehicles cannot be licenced for London. The cars that can be are the ULEZcompliant, “zero-emissions capable” plug-in hybrids with both petrol and diesel engines, which came on stream in 2018.

The E300de uses the 1,950cc, 194bhp version of the OM 654 four-cylinder diesel engine introduced in 2016. Pure diesel E-classes have an upgraded 1,993cc version with integrated starter-generator, giving it a partial 48-volt electrical system, but the PHEV powertrain remains the same.

Other significant changes are to the electronics, where the E-Class now boasts the next generation of driving assistance systems and the latest MBUX (Mercedes-Benz User Experience) infotainment system. MBUX is based around two large 10.25in screens mounted side by side to give a widescreen look. As an option, two larger 12.3in screens are available. The high resolution of the screens means the information in the instrument cluster and on the media display is extremely clear and legible.

The E300de’s 2.0-litre diesel engine produces 194bhp and 400Nm of torque. It is mated to an electric motor with 122hp of power and 440Nm of torque, giving a combined system output of 306hp and 700Nm. The diesel hybrid powertrain is available with estate body too, which may be preferable if you need more luggage space.

The battery pack is centrally mounted, and low down in the structure below the back seat. But there is some loss of boot space – it’s 370 litres against 540 litres for a standard diesel or petrol model – with a notable “step” half-way back into the boot. This restricts luggage-carrying abilities, which is not helped by the two charging cables, each housed in a bulky bag. We were able to get our test cases into the car – but only just.

The E300de has a claimed a fully electric range of 38 miles for the saloon. It has a battery capacity of 13.5 kWh and can be charged from 10 to 100% in under two hours with a 7.4 kW charger. The E 300 de AMG Line Edition saloon starts at £47,480 while the Estate costs £49,480.

The 2016 E-Class was launched with a large amount of autonomous features, and although the law doesn’t yet allow them to be used to the fullness of their capabilities, the latest facelift adds a new steering wheel with sensors, which means that the driver just has to touch the wheel, without any steering input, to maintain “handsoff” steering, for example when negotiating road works. If the system detects that the driver is not touching the steering wheel for a certain time, visual and audible warnings are issued, and finally Emergency Brake Assist is activated if the driver continues to be inactive.

In addition, the E-Class now has major enhancements to the anti-theft systems. The Urban Guard packages enable all-round monitoring of parked vehicles. Urban Guard comprises an anti-theft alarm system, tow-away protection with visual and audible warning in the case of a detected change in position, an alarm siren, interior monitoring (which triggers in the case of movements in the interior) as well as preinstalled theft and parking collision detection.

Vehicle sensors register when the parked and locked vehicle is bumped or towed – or when someone attempts to break in. If the service is active, the driver immediately receives detailed information via the Mercedes me App. This tells the driver how severe the parking damage is and in which area of the vehicle it occurred. As soon as the vehicle is restarted, this information is also shown once on the media display.

Urban Guard Vehicle Protection Plus contains a hidden tracker system for pinpointing the position of stolen vehicles, making it possible to recover the vehicle even if the thief has deactivated the vehicle tracking function. This takes place in cooperation with police.

verdict

The diesel hybrid mercedes-benz e300de is the most economical e-class of all time.

It gives diesel fuel economy and range, while being compliant with London licensing requirements. You will avoid ULEZ charges until TfL realises it needs another revenue stream, but Congestion Charge exemption will go in October 2021, so it’ll cost £15 a day to drive into Central London. Improvements this time around are subtle. The introduction of 48v electrics will give greater capabilities across the range going forward, though this change doesn’t apply to the E300de model. Nevertheless, more user-friendly autonomous systems will come in handy when you’re grinding your way through 50mph motorway contra-flows, while improved anti-theft systems are something that hopefully will only deliver peace of mind, and remain untested in daily use. The visual displays are improved, though the Mercedes display was the best on the market even before this facelift. On the downside, the replacement of the old rotating Comand controller with a pinch and stretch touch pad takes some getting used to – though in practice the new steering wheel controls are easier to navigate. And the battery pack still creates a problem in the boot – the shape is awkward and capacity is reduced significantly, especially with the need to carry two charge cables.