Best MHEVs

Choosing a mild hybrid is the most affordable way into a car that offers a small electric boost. Here are some of the best MHEVs available

Gavin Braithwaite-Smith
Apr 13, 2022

Mild hybrid cars are growing in popularity. In 2021, nearly 300,000 mild hybrid vehicles - also known as MHEVs - were registered in the UK, making them more popular than diesel, electric, hybrid and plug-in hybrid cars.

Sales of petrol MHEVs were up 66.2%, while diesel MHEVs sales increased by 62.0%. These figures are even more impressive when you consider that diesel and petrol sales were down 48.1% and 15.7% respectively.

We should point out that mild hybrid cars were starting from a low base, but the fact remains: MHEV is the fastest-growing sector of the new car market. It’s also the most affordable and easy-to-understand entry in the world of part-electrified cars. However, as 'mild' suggests, MHEVs offer less electric assistance than other types of hybrid, so they can't travel for any distance on electric power, but instead offer slightly reduced fuel consumption compared with equivalent models that lack the MHEV tech.

Best mild hybrid cars

What is an MHEV?

MHEV stands for Mild Hybrid Electric Vehicle. As we pointed out above, a car with a mild hybrid setup uses a traditional combustion engine to provide power to the wheels, but also has a small electric motor to assist with acceleration.

Unlike full hybrids (sometimes referred to as self-charging hybrids or conventional hybrids) and plug-in hybrids, you cannot drive an MHEV using battery power alone. In most cases, an MHEV features a 48-volt battery, which is supplementary to the car’s standard 12-volt battery.

Benefits include smoother engine restarts, improved fuel economy and more powerful acceleration. According to figures published on our sister site DrivingElectric, a 48-volt mild hybrid system could deliver a 25% increase in low-engine speed punch, a 10-15% boost in fuel economy and a 25% reduction in CO2 emissions compared to a traditional 12-volt system.

More advanced MHEV systems feature engine switch-off technology to further increase fuel economy. On some Audi models, for instance, if the driver takes their foot off the accelerator at a speed between 34.2mph and 99.4mph, the car can coast for up to 40 seconds with the engine switched off. During slow coasting, the stop-start system is activated at speeds of up to 13.7mph.

In other cases, the mild hybrid system takes the form of an integrated starter motor (ISG) which acts as both a generator and starter motor. You’ll find such a system in some Suzuki models - just look for the SHVS (Suzuki Hybrid Vehicle by Suzuki) badge.

The engine stops for longer periods than conventional stop-start systems and operates at speeds of up to 10mph. The conventional starter motor is used only when the engine is cold; the ISG unit is used under all other conditions. Under braking, the system will restore energy to the supplementary lithium-ion battery and conventional 12-volt battery.

One of the advantages of a MHEV is that you’re unlikely to notice the technology. You’ll appreciate the smoother starts, coasting potential, improved fuel economy and lower emissions, but you can leave the tech to its own devices.

A mild hybrid vehicle might be more expensive to buy than a car with a standard petrol or diesel engine, but you’ll begin to recoup the difference over a period of time. MHEVs are also significantly cheaper than full hybrid and plug-in hybrid vehicles.

We’ve pulled together a list of some of the best MHEVs available below - from city cars to large saloons and supersized SUVs.

1. Ford Puma

Ford Puma side view

Used deals from £17,539
Monthly finance from £321*

The Ford Puma is one of the latest compact SUVs to hit the market. It also happens to be one of the best. It’s as fun to drive as the closely related Ford Fiesta (that’s high praise, as the Fiesta is both comfortable and enjoyable to drive), it looks funky and it comes with plenty of standard equipment.

Ford’s EcoBoost Hybrid system uses a belt-driven integrated starter/generator (BISG) instead of a standard alternator. The BISG also acts as a motor, using battery power to deliver better performance, particularly at low speeds.

Regenerative braking reclaims energy that would otherwise be wasted as the car slows down and turns this into a boost for when you accelerate. The mild hybrid tech is standard on the 1.0-litre EcoBoost engine; you can expect to see around 50mpg fuel economy in daily use.


2. Kia Rio

Used deals from £17,486
Monthly finance from £320*

The Kia Rio is a rival to superminis like the Ford Fiesta, Vauxhall Corsa and Renault Clio. Aside from the entry-level version, all models come with a generous level of equipment, plus you get the reassurance of a seven-year warranty - so even if you get a three-year-old model - the age at which most rival manufacturers' warranties run out - you should still have four years of Kia cover. The top-spec ‘3’ and GT-Line S models also benefit from a 48-volt mild hybrid system.

It’s a clear demonstration of how a MHEV can deliver lower running costs than a conventional petrol car. Not only is the 1.0 T-GDi engine more powerful in mild hybrid form, but it’s also more efficient than the lower-powered version. CO2 emissions are as low as 118g/km on the ‘3’, with claimed fuel economy of 54.3mpg, meaning that you shouldn't have to fill up the Rio often.


3. Suzuki Swift Sport

Used deals Limited stock

The Suzuki Swift Sport provides the proof that a mild hybrid system can be used to great effect in a hot hatchback. Although some Suzuki models feature the standard 12-volt ISG system, the Swift Sport gets a superior 48-volt setup.

It consists of a 48-volt lithium-ion battery, ISG and DC/DC converter to power components requiring lower voltage, including lights, audio and air-conditioning. The ISG acts as a generator and starter motor and assists the 1.4-litre turbocharged petrol engine during acceleration. The system weighs just 15kg and is hidden under the front seats to assist with weight distribution.


4. Fiat 500

Used deals from £10,990
Monthly finance from £0*

The Fiat 500 Mild Hybrid was introduced in 2020 and sits alongside the new Fiat 500 Electric. It features an integrated belt starter generator combined with an 11Ah lithium-ion battery mounted to the 1.0-litre three-cylinder petrol engine.

As well as a small boost in acceleration, the mild hybrid tech delivers claimed fuel economy of 53.3mpg and CO2 emissions of just 88g/km. This makes it the most economical Fiat 500 you can buy, short of buying the considerably more expensive electric version.


5. Jaguar XE

Used deals Limited stock

The Jaguar XE is a desirable alternative to upmarket cars like the BMW 3 Series, Mercedes C-Class and Audi A4. It’s the closest rival to the 3 Series in terms of driver appeal and, following an update in 2019, it’s now better and more affordable than ever. But Jaguar didn’t stop at the 2019 update.

A year later, it introduced a new 2.0-litre four-cylinder diesel engine with 48-volt mild hybrid technology. Claimed CO2 emissions of 127g/km and fuel economy of 58.5mpg are seriously impressive figures for a car of this nature; mild hybrid tech can even breathe new life into diesel cars.


6. BMW X3

Used deals from £39,780
Monthly finance from £0*

Mild hybrid technology is still relatively new, so you might have to search for an updated model when searching for your next used car. Take the BMW X3, which was refreshed in 2021 in the face of competition from SUV rivals like the Volvo XC60 and Audi Q5.

Every petrol and diesel engine now features assistance from a mild hybrid system featuring a 48-volt electrical system and belt starter-generator. Fuel economy and low-engine-speed acceleration are now better than ever, while the stop-start system is more active, with the engine happy to coast whenever possible. As a result, the new BMW X3 will deliver better fuel economy than a pre-update model.


7. Audi A6

Used deals from £24,949
Monthly finance from £0*

Audi’s 48-volt mild hybrid system is one of the best on the market. Launched on the A8 luxury car, the tech is now filtering down to Audi’s smaller and more affordable models, including the A6. All models other than the 50 TFSI e plug-in hybrid feature the tech, but the system varies depending on the model.

The six-cylinder 50 TDI and 55 TFSI models come with the superior 48-volt mild hybrid system, which allows the engine to shut down when coasting at a speed between 34mph and 99mph. The four-cylinder engines use a 12-volt system, but all versions should deliver better fuel economy than an equivalent petrol or diesel engine without the tech.


8. Range Rover

Used deals from £84,995
Monthly finance from £2,922*

Manufacturers are in a rush to introduce MHEVs as they seek to lower their overall CO2 emissions. Take Land Rover, which added a mild hybrid diesel to the outgoing Range Rover range - even though a new model is due in 2022.

The mild hybrid 3.0-litre D300 diesel engine in the outgoing Range Rover is capable of achieving up to 33mpg fuel consumption, with CO2 emissions of 225g/km. The D350 returns figures of 30.8mpg and 241g/km, and while these figures aren’t as strong as for the D300, it makes it faster than the previous large V8 engine with the efficiency of a smaller six-cylinder unit; an example of mild hybrid tech being used to good effect in a luxury SUV.


*Representative PCP finance - Ford Fiesta:

48 monthly payments of £192
Deposit: £0
Mileage limit: 8,000 per year
Optional final payment to buy car: £2,923
Total amount payable to buy car: £11,926
Total cost of credit: £2,426
Amount borrowed: £9,500
APR: 9.9%

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