• #Hybrids
  • Electric cars
  • Mar 23, 2021

Which is better, an electric car or hybrid? If you need to replace a car right now and don't feel ready to take the plunge, could a plug-in hybrid (PHEV) be your stepping stone to electric driving? Does it give you the 'best of both worlds'?

It's a tempting decision. Plug-in hybrids are slightly less expensive than a BEV (a full electric car) and there’s less to get your head around in terms of making longer journeys. If you are replacing a petrol or diesel car, the PHEV can sound appealing, we think having one on your driveway will be something you come to regret.

Let's look at the three main selling points of plug-in hybrids to see whether a PHEV really lives up to your expectations.

Selling point #1: Most trips are emission-free

The lure of the plug-in hybrid is this: With a 30-mile battery, PHEV drivers will be able to do their commute on electric power alone Monday to Friday, but they’ll still have a car capable of conveniently driving much longer distances at the weekends.

Sounds good, doesn’t it? The problem is PHEVs may have an advertised range of around 30 miles, but in real-life would do much less than this. Real-world ranges are roughly 80% of the official (WLTP) calculations, so you might get nearer 24 miles electric driving. With the average UK car trip being between 7 and 9.2 miles, that's only just about enough to cover an average return trip.

After 24 miles, your PHEV is just a petrol car lugging around a big, heavy battery pack. You're likely to achieve around 40mpg with a Mitsubishi Outlander PHEV according to a review by carbuyer.co.uk. This figure drops into the 30s if you do motorway driving, according to a review from The Engineer. This might be far less than the car you traded in, and your carbon and cost savings will disappear with each trip. Trips over 50 miles count for 25% of the average driver's mileage.

Driven in battery-charging mode (as you might do to charge up ahead of using electric mode in low-emissions zones) the PHEVs produced up to 12 times more emission than advertised.

If your goal was to do your bit to reduce toxic pollution in our streets, you might unwittingly be doing the opposite.

Mitsubishi Outlander PHEV was 2020's top-selling plug-in hybrid SUV in Europe

Part of the real-world problem of PHEVs is lack of rapid charging. There's a lot more waiting around to recharge the battery if you're using the public charging network. For the Outlander, DC charging from a rapid unit is available but limited to 22 kW - meaning roughly 1 mile per minute can be added. This compares to up to 150kW chargers for BEVs, although some older BEV models are limited to 50kW.

Without big compromises in waiting time, increasing your electric miles in a PHEV en-route is much more tricky than it is for a BEV.

BEV owners do 90% of their charging at home while they sleep. PHEV drivers can also charge at home. A PHEV’s small battery can be refilled even from a regular socket in around six hours. PHEVs also qualify you to switch to a cheaper EV tariff. Installing a dedicated home charger reduces your charge time to around four hours.

Selling point #2: PHEVs offer control

If you can leave your house fully charged and rarely need to go over 30 miles in a day, will a PHEV work then? Not necessarily. Most plug-in hybrid models automatically turn on the petrol/diesel engine at start-up on a cold day, or let it kick in if the driver accelerates hard.

Outlander PHEV owners say “If you switch the heating on the engine kicks on automatically, so I tend to use the heated seats instead unless I have the kids with me”.

A PHEVs emissions will depend on the driver's behaviour. But the driver doesn't have full control, even doing uphill sections on a normal journey and in order to stay warm. On a fully charged battery in optimal conditions, PHEVs may emit 28-89% more CO2 than advertised.

The downside of two powertrains, is that you have to pay for, and maintain both. A study by Which? found that plug-in hybrids proved least reliable, with 15 per cent of 55,000 drivers surveyed suffered a problem with their car. These were mostly minor faults on relatively new cars, but it highlights that more parts means a greater chance of something going wrong on a PHEV.

As today's PHEVs reach the secondhand market this will inevitably be more of an issue. In contrast, BEVs are much less of a lottery for a secondhand buyer. The health of the battery can be checked using a plugin ‘dongle’ device.

BEV - the pros

  • Longer EV range
  • Lowest running costs
  • Zero-tailpipe emissions
  • Near-silent running
Cons: Charging can add time on longer journeys

PHEV - the pros

  • Normal petrol driving range
  • Possibly reduced running costs
  • Potential for lower CO2 emissions
Cons: Low mpg for the petrol miles. As you can't rapid charge, limited electric miles per day.

Selling point #3: I’ll be exempt from Congestion Zones in a PHEV

For now, yes. But from October 2021, only pure-electric zero-emission cars will be exempt. London’s Clean Air Zone (CAZ) has just been joined by a scheme in Bath and Birmingham will start later this year. In London, PHEVs will pay £11.50 to enter the London Congestion Charge zone during the week. Even BEVs will have their exemptions removed in December 2025, but that gives BEV drivers over four more years longer.

It seems that hybrids, from self-charging to PHEVs, are much more prominently advertised on our screens than full electrics, so it may surprise you that sales of fully electric cars have accelerated faster in the last year and overtaken PHEVs in number in 2021. BEVs are up nearly 55% compared to 28% for PHEVs compared to this time last year.

SMMT data shows that BEVs are growing faster than PHEVs in the last year

A survey by SMMT found the biggest factors holding BEV buyers back are higher purchase prices (52%), lack of local charging points (44%) and fear of being caught short on longer journeys (38%).

Are fully electric cars ready?

The SMMT study back in September 2020 found a third (37%) were optimistic about buying a BEV by 2025, 44% don’t think they’ll be ready by 2035, with 24% saying that they can’t ever see themselves owning one. With better cars, lower price tags and a better charging network, these attitudes are set to change fast.

In the last year, fully electric BEVs have arrived on the market with larger and larger ranges from a single charge. The majority of more affordable BEVs available have a real-world driving range of 160-250 miles from a single charge.

At the same time the public charging network is improving with updated chargers and more locations, meaning your longest journey shouldn’t feel determined by the size of your battery pack. In a great sign of things to come, electric forecourt builder Gridserve has recently come on board and promises to rapidly help the ageing Ecotricity motorway network get up to speed.

There’s no denying that with a BEV you will need to plan ahead for longer journeys. Ensuring that a suitable charging location is available or adjusting your routes and time to accommodate a 30-40 minute rapid charge en-route. But, from the perspective of most current EV drivers, the benefits far outweigh the disadvantages. Being able to charge at home overnight when electricity is cheap reduces your cost to as little as 1p per mile.

If you can’t home charge but you do commute to work, workplace charging is equally convenient. If you are lucky enough to have a company car allowance, the benefit in kind for electric cars is only 1% for the next two years.

There is no doubt that the car buying process has become even more complex. Electric cars are still unfamiliar technologies to many, so deciding which would fit your lifestyle and usage patterns, prove most cost effective to run and have most impact on air pollution and carbon emissions is not a simple task.

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