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Don't be fooled! Mild hybrids aren't 'real' hybrids - the term for the minor fuel-saving technology is just a (really) bad marketing joke | Opinion

The new Mazda MX-30 M Hybrid small SUV isn’t quite as ‘hybrid’ as its name suggests.

There are few things that grind my gears more than mild hybrids. As far as I’m concerned, the term – not the minor fuel-saving technology – should’ve never existed in the first place, because it has had the potential to deceive scores of new-vehicle buyers for years now.

It’s no secret that electrification is the future, and new-vehicle buyers are already turning to ‘self-charging’ hybrids (HEVs), plug-in hybrids (PHEVs), battery-electric vehicles (BEVs) and even hydrogen fuel-cell electric vehicles (FCEVs) in increasing numbers.

Which brings me to where mild hybrids (MHEVs) fit into the electrified future: nowhere. You see, mild hybrids aren’t ‘real’ hybrids. Instead, the term behind them is a prime example of deceptive marketing.

To understand why, though, it’s important to establish what makes a mild hybrid a mild hybrid – you can thank Chevrolet for their 2005 establishment – and how that significantly differs to self-charging and plug-in hybrids, so bear with me as I get technical for a moment.

Mild hybrid is a widely used term for a mildly electrified powertrain, with it typically pairing an internal-combustion engine (petrol or diesel) with a 12V, 24V or 48V battery and an integrated starter-generator (ISG), which replaces both the starter motor and alternator.

2005 Chevrolet Silverado Hybrid 2005 Chevrolet Silverado Hybrid

Depending on the application, a mild hybrid can turn the engine off when the vehicle is coasting, braking or stationary, with it able to switch the unit back on very quickly, when necessary. So, think of it as offering extended idle-stop (or stop-start) functionality.

In certain scenarios, a mild hybrid can also give the engine a small electric boost via its integrated starter-generator, which is not capable of driving the wheels on its lonesome. That said, regenerative braking is supported, to keep the battery charged.

Therefore, a mild hybrid is what’s known as a ‘parallel hybrid’ and an almost insignificant one at that, which basically means it offers negligible fuel savings, ranging from as high as nearly 1L/100km to as little as 0.1L/100km – and that’s not in real-world testing.

Comparatively, a ‘series hybrid’ (electric motor/s exclusively drive/s the wheels, and an engine charges the battery), such as the Nissan Qashqai ePower small SUV, can save litres of fuel on the combined-cycle consumption test over a traditionally powered vehicle.

Better yet, a ‘series-parallel hybrid’ (electric motor/s and/or an engine drive the wheels, with the latter also able to charge the battery), like the Toyota RAV4 mid-size SUV’s self-charging Hybrid or plug-in Prime variants, can save even more fuel in official tests.

2020 Toyota RAV4 Hybrid 2020 Toyota RAV4 Hybrid

If all of that makes sense, you’ve no doubt started to realise that not all hybrids are created equal, and mild hybrids are undoubtedly the weakest of them all – and by some margin.

Yes, I fully understand that the lack of capability is literally spelt in their name, but mild hybrids benefit from their association with the all-important ‘hybrid’ word – it’s half their name, in fact.

This, of course, sets a dangerous precedent, as a new-vehicle buyer will inevitably walk into a showroom, stumble upon a mild hybrid and drive away in it thinking that they’ve bought a self-charging hybrid when they haven’t.

To make matters worse, some brands go a step further than just pushing the ‘mild hybrid’ term. For example, Maserati calls its mild-hybrid Levante large SUV the Hybrid. Yep, I wish I was joking.

Then there’s the case of Mazda and its MX-30 small SUV, which is available with a mild-hybrid powertrain that’s dubbed M Hybrid. Does the ‘M’ stand for ‘Mazda’ or ‘Mild’? Either way, new-vehicle buyers are likely to mistakenly get excited by the ‘Hybrid’ part.

2022 Maserati Levante Hybrid 2022 Maserati Levante Hybrid

It’s not all bad, though, as Audi extensively uses the more discrete MHEV acronym in its marketing materials, while rival Mercedes-Benz keeps the mentions of mild hybrid and MHEV to a minimum by instead pushing its EQ Boost branding for the technology.

Which brings me back to my first point: fuel-saving technologies are absolutely worthwhile, particularly during this tricky transition to zero-emissions motoring. After all, any step towards reducing the world’s reliance on fossil fuels is a step worth taking.

That said, brands – and media – need to stop treating mild hybrids like are what their name implies: a hybrid (self-charging or plug-in), because they’re just not.

I’d suggest we all come with a new term for mild hybrids, one that takes the focus off their negligible real-world contributions and puts them in the category as idle-stop functionality (stop-start systems), cylinder deactivation technology and other minor fuel-saving features.

After all, if you’re buying a hybrid because you want a hybrid, you should have no doubt that the one you buy is a ‘real’ one, because if you have been deceived, you’ll find out the hard truth at the one you don’t want to: the petrol station. That wouldn’t be fun, would it?