The smallest Mercedes is a huge seller in the UK, and the addition of this new A250e will only broaden its appeal. The name is a smidge misleading – this is a plug-in hybrid, not a fully electric car, but it will do a reasonable distance with naff-all coming out of the tailpipe.Mercedes quotes around 40 miles on the new WLTP cycle, and it seems pretty plausible if you keep away from the motorway. Or resist absolutely flogging the thing out of roundabouts. This is one of the quickest A-Classes on sale, with its combination of a 1.3-litre petrol engine and an electric motor providing a peak output of 218bhp, good for 0-62mph in 6.6secs. It perhaps feels quicker still. The top speed is 146mph, and it’ll do an impressive – but range quenching – 87mph on electric power alone.Both engine and motor operate on the front axle, so there aren’t any all-wheel-drive tricks here. There’s an eight-speed twin-clutch gearbox strapped to the engine, one that’s much nicer than the seven-speed transmission you’ll find in the A200 petrol that uses this dinky 1.3-litre sans electricity. The 150kg battery lives beneath the rear seats, with the fuel tank moved back a bit to impede, albeit slightly, on boot space. You lose around 50 litres of carrying capacity, but the load bay does stay flat. Helping squeeze everything beneath the A’s compact body is a shortened exhaust system, with the tailpipe pointing downwards somewhere beneath the driver with extra sound insultation to ensure it’s no louder for those sat up front. A nerdy thing to point out? Absolutely, but given previous A-Classes were famed for exceedingly clever packaging, it’s a nice nod back to the model’s early days to see how the engineers have squeezed so much powertrain beneath the floor.It’s instantly one of the most appealing non-AMG A-Classes thanks to how hushed it is inside. Our previous experience of this engine is that it can be quite thrashy when it’s worked hard, so the fact the A250e seems so keen to default to electric and keep the internal combustion unit hushed is very welcome. Like any plug-in hybrid, you’ve a choice of driving modes. You can choose Electric, to keep the car steadfastly emissions-free unless you really accelerate hard, while a battery save function allows you to kick the engine into life on longer journeys to save those hushed miles for when you’re back in town. Then there’s a pair of hybrid modes – Comfort and Sport – with predictably different attitudes to how often the engine should function. While your own personal use case will dictate which modes you favour, the car is typically best left in Comfort where its brain juggles the power as it sees fit and gives you one less thing to fret about. Likewise the adjustable energy recuperation for the brakes, which you can strengthen or loosen with the steering wheel paddles when you’re in Electric mode.However, hold down one of the paddles for a few seconds and it’ll go into an Auto function that adjusts the level of brake regen as the road ahead dictates, using the cameras to see if there’s a car ahead and the sat nav to predict changes in speed limit. Again, just leave it in this mode and let the car do the thinking for you. After all, if you’re spending the £32,000 this car’s likely to cost, you’ve forgone proper hot hatches and chosen something quite different. So you’ll revel in how relaxing a silent car can be and quickly switch to the mindset hybrids often nurture; the one where you calm all of your inputs right down, desperate to avoid using the engine. Driving engagement of an entirely different kind, basically, one only encouraged by how tangibly heavier the A250e feels in corners. It’s a car that elicits smoothness from its driver, not silliness.Yes, but with the caveat that like a lot of plug-in hybrids – especially smaller ones – it feels like a stepping stone to appease stringent emissions regulations rather than a vision of the future. Now that manufacturers are extracting properly usable range from electric cars, a car like this perhaps feels a heavy compromise, especially if the battery drains on a bigger journey and you’re carrying it around without much benefit. This represents one of four types of electrified Mercedes that’ll be offered, though. ‘EQ Power’ are plug-in hybrids like the A250e. There’s also ‘EQ Boost’ (cars with a mild-hybrid system that powers the ancillaries rather than the wheels), ‘EQ Performance’ (petrol-electric AMGs that favour performance over range) and straight ‘EQ’, the full-strength EVs like Merc’s EQC crossover.It’s hard to say. Merc’s engineers are certainly thinking about it, but they face a conundrum. To offer the 300-mile range customers need, the car will have batteries shoved into every orifice. If the car is to be packaged more usefully, then the range will be 200 miles or less its appeal will dwindle. Dinky Mercedes EVs will likely end up a more bespoke affair then just squeezing batteries into an existing model, then.The battery can reach full charge in as little as 25 minutes. The 250e powertrain is also available in the A-Class saloon and B-Class people carrier thingy (pictured above). And this is one of 20 EQ-badged Mercs you can expect by the end of 2020.