Thinking of making your next car an electrified one? Well there’s an awful lot of choice available to you these days. In this feature, the experts at Car & Driving guide you through a few of your options – mild hybrid, full-hybrid, Plug-in PHEV hybrid, full-EV and Hydrogen fuel cell.
Let’s start with the most affordable category of electrification these days, that for Mild Hybrids. Mild hybrid technology differs from full-Hybrid technology in that with a mild hybrid, the car is never running fully under electric power. A small battery secreted beneath the front or rear seats powered by brake regeneration merely helps out with energy provision – and slightly boosts acceleration. That means the efficiency returns of a mild hybrid aren’t nearly as good as a Prius-like full-hybrid – but then mild hybrid models cost a lot less.
Full-hybrid tech is slightly different – the kind of thing pioneered by Toyota’s Prius back at the turn of the century and perfected (primarily by Toyota and Lexus) in the decades since. The engines on offer in this category can’t be plugged in for a degree of all-electric range, so they’re sometimes called ‘self-charging hybrids’ to differentiate them from the PHEV variety. Full-hybrid tech uses a larger battery than would a mild hybrid engine, which allows the powerplant to switch in and out of full-electric mode in town traffic.
PHEV (‘Plug-in Hybrid Electric Vehicles’)
But if you want to go any real distance on electrified power yet retain the peace of mind that comes with the extended driving range you can currently only get from a conventional combustion petrol or diesel engine, then what you’ll need is a PHEV Plug-in hybrid. This uses a larger battery still which will typically give you an all-electric driving range of around 30 miles – provided you keep the car fully charged. And when the range is used up, the engine will seamlessly switch into combustion mode.
Because the current WLTP industry fuel and CO2 measuring system takes a PHEV model’s all-electric driving range into account, incredible-sounding three-figure combined cycle fuel economy figures and sub-50g/km CO2 readings are routinely quoted for PHEV models. You probably won’t achieve these in typical day-to-day motoring, but the important thing is that the government believes them, which is why Benefit-in-Kind taxation rates on PHEV models are far lower than the rates applied for other kinds of combustion-engine vehicle.
Full-EVs (‘Electric Vehicle’)
But what none of these various hybrid options can do is totally eradicate harmful CO2 emissions and noxious fuel pollution. To achieve that, the most obvious route is to get yourself a full-EV fully electric model (sometimes known as ‘BEVs’ – ‘Battery Electric Vehicles’). These kinds of cars will still only be suitable if you have off-street parking and only typically undertake short-to-medium-length journeys, but they’ve come on a long way since you last looked.
Stung into action by US brand Tesla, the major makers have now developed full-EVs that really can go a decent distance between charges. The better smaller models can now travel over 200 miles between charge-ups, while for large luxury electric vehicles (usually luxury SUVs), the figure is closer to 300 miles. Because a full-EV has a much larger battery than a PHEV, it will of course take much longer to charge up. Just how long depends of course on the type of supply you use. The industry likes to quote recharging time figures from public rapid chargers that can typically replenish an EV model’s battery from empty to about 80% in under 45 minutes. These are difficult to find though – and will be until a better public charging infrastructure can be established, though things are progressing quickly in that regard. In the meantime, a typical 7kW wallbox installed in your garage will easily be able to replenish your EV overnight.
Hydrogen Fuel Cell
Not everyone likes the idea of electrification though. Some people’s perspective is that combustion engines are intrinsically polluting and basically inefficient and that any kind of plug-in EV merely moves the environmental pollution point from the vehicle to the power station that charges it. These are the people who will be most interested in the idea of Hydrogen fuel cell power – which is predicted to be the next big thing after EVs.
Fuel cell vehicles combine hydrogen and oxygen to produce electricity, which runs a motor. Since they’re powered entirely by electricity, fuel cell vehicles are considered electric vehicles (“EVs”) - but unlike other EVs, their range and refuelling processes are comparable to conventional cars and LCVs. Converting hydrogen gas into electricity produces only water and heat as a by-product, meaning fuel cell vehicles don’t create any tailpipe pollution when they’re driven. In fact, it’s claimed that they actually clean the air around them as they drive.
A hydrogen refill takes about the same amount of time as filling the tank of a conventional combustion engine petrol or diesel model - around five minutes. That's the good news. The bad news is that finding a hydrogen station to facilitate that process is likely to be a challenge. At the moment, there are only a handful of hydrogen filling stations in the UK, though there are plans to increase their number to 65 by the year 2025. There are currently only two Hydrogen fuel cell models on the market – the Toyota Mirai and the Hyundai NEXO, but you can expect that to change as the refuelling infrastructure improves.
So, lots of choice then. The EV route that works best for you will depend on lots of factors – to name just a few things, your budget, your motoring preferences, whether you have off-street parking, the length of journeys you typically do, your environmental outlook on life and so on.