Petrol, diesel, hybrid, plug-in hybrid or electric – which is the cheapest to own?

You might think that the lower running costs of an electric or hybrid car will make it the cheapest ownership prospect. We reveal that’s not always the case...

25 October 2018
New Hyundai Ioniq vs Toyota Prius

Do we have the infrastructure for an electric future in place? 

While the latest battery technology has eased the range anxiety that has always been a concern for most potential electric car buyers, the ability to get to or find a charging point can still be a worry. However, the UK’s public electric infrastructure is growing apace. Today, there are 10,264 public charging points across the UK, with connectors to charge up 17,615 cars. 

Still, that’s way short of the 300,000 electric cars that the Transport Research Laboratory estimates will be on our roads in 2030 – and it predicts that could soar to 12 million by 2040. 

Renault Zoe

To further boost the infrastructure, the Government has proposed making it mandatory for chargers to be fitted to new flats and houses in its Road to Zero strategy. This also said new lamp-posts on roads with parking must have built-in chargers. 

Transport secretary Chris Grayling claims the proposals are the most significant for road transport since the invention of the car and will ensure that drivers of electric cars “ find it easier to recharge their vehicles than motorists today who have to visit a filling station”. The proposals are part of a £400m scheme to boost the use of battery-powered vehicles. Some £40m of that will go to the development of low- cost wireless charging tech, to aid the 27% of UK drivers without a garage or off-street parking. 

Renault Zoe charging

What Car? says…

Simply switching to an electric, hybrid or plug-in hybrid car won’t necessarily save you money. In fact, if you choose one with a high list price and steep depreciation, you’d be thousands of pounds worse off than if you’d bought a petrol or diesel alternative. That said, some electric cars are conspicuously good value. The Hyundai Ioniq Electric tops our league of family cars, with a three- year cost that’s more than £6000 less than that of the Volkswagen e-Golf and some £1000 cheaper than for its Ioniq Hybrid sibling. 

While petrol models are the cheapest in two of the other three categories, don’t discount the hybrids they beat, because they’re likely to work out more affordable if the majority of your driving is in urban areas. The Toyota Yaris proves the point, with the hybrid coming out ahead of the regular petrol version, despite the former’s thirst at higher speeds. 

Diesel is still the best choice if you’re after a large SUV, as the Mazda CX-5 proves. However, the fact that the hybrid Toyota RAV4 and petrol Peugeot 5008 aren’t all that far behind on running costs means you don’t have to stick with diesel if you don’t want to. 

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Electrified cars: the jargon explained

Everything you wanted to know about hybrid, fully electric and fuel cell cars, but were afraid to ask

Nissan Leaf, Volkswagen e-Golf and Renault Zoe

Electric and hybrid vehicles are more popular than ever, and although it’s still a niche market, more than 500,000 such cars have been sold in the UK.

Sales have picked up dramatically this year, with more than 114,000 alternatively fuelled vehicles (AFVs) registered up to the end of September – up 21.7% on the same period last year.

But with the proliferation of these cars, so too has come a whole range of terms surrounding them. Here, we explain them in plain English.

Types of cars:

Alternatively fuelled vehicle (AFV), electrified car

Any car that doesn’t solely use a conventional petrol or diesel engine falls under these umbrella terms.


Electric vehicle (EV)

This term – along with battery electric vehicle (BEV) and electric car – is used for cars that run solely on electricity and therefore produce no exhaust emissions, a leading example being the Nissan Leaf, our 2018 Electric Car of the Year. Instead of a petrol or diesel engine, they have an electric motor that is powered by batteries, which you charge by plugging the car into a socket.

For: Zero-emissions running; far quieter on the road; much cheaper to refuel; EVs with a list price below £40,000 are exempt from road tax and the London Congestion Charge.

Against: Ranges aren’t comparable with those of other types of car; long charging times; poor predicted residual values.

Nissan Leaf front

Hybrid

Any hybrid car combines a conventional petrol or diesel engine with an electric motor and batteries. Although not as ‘green’ as fully electric cars, hybrids generally consume less fuel and produce less CO2 than conventionally powered cars.

The most common type is the parallel hybrid – sometimes known as a self-charging hybrid – and is found in cars such as the Toyota Prius. The engine is still the main power source, but the wheels can be powered in three different ways: either directly by the engine, by the electric motor alone, or by both working together. You never need to charge these hybrids. Most can run on electric power only for just a few miles at low speeds.

For: They’re really economical for stop-start city driving, because the electric motor gets the most use and the regenerative braking boosts the batteries whenever you decelerate or use the brakes.

Against: Fuel economy tends to nosedive out of town, because the batteries make the car heavy and the electric motor will soon run out of charge at higher speeds and under hard acceleration.

Toyota Prius front

Plug-in hybrid electric vehicle (PHEV)

As the name implies, this type of hybrid can be plugged into an electric outlet to recharge its batteries, as well as being charged on the move. One of the most popular so far is the Mitsubishi Outlander PHEV.

In effect, it’s a halfway house between a parallel hybrid and a full electric vehicle. Although it has a conventional engine, it also has larger batteries than a parallel hybrid and can drive for longer distances and at much higher speeds on electric power alone – up to 30 miles and at least 70mph in some cases.

For: Has a longer range than an electric car; cheap to use for short, urban journeys that don’t deplete the batteries.

Against: Batteries add weight, making fuel economy poor on motorway runs once the batteries are depleted; need to recharge batteries more often than a pure EV, which will have a longer range; need to plug in to properly charge, unlike parallel hybrids.

Mitsubishi Outlander PHEV

Range extender

These cars run on electricity but have a small petrol or diesel engine that never powers the wheels. It is used only to produce electricity to recharge the batteries. The aim of range extenders such as the BMW i3 REX (there’s also a fully electric version) is to provide an extra 70 to 100 miles of range once the batteries have been depleted, giving extra flexibility between charges.

For: Better than a parallel hybrid for longer, out-of-town journeys, because it drives on electricity only; no range anxiety, thanks to the engine.

Against: Extra weight of engine means the car isn’t very economical when it’s generating power, so the overall range will be less than that of a comparable regular electric car.

BMW i3 front

Hydrogen fuel cell vehicle

These cars mix hydrogen with oxygen in a fuel cell to produce electricity. They’re rare – the Toyota Mirai being one of the few you can buy – because they’re expensive and there are fewer than 20 public hydrogen refuelling stations in the UK.

Hydrogen-powered cars take less than five minutes to fill up, have a greater range than battery-electric cars and only emit water from their exhausts.

They are therefore seen by some people as the best longterm solution to emissions-free driving. However, the processes used to generate and transport hydrogen make them less ec0-friendly overall than conventional electric cars at present.

For: Quick refuelling time; range between fill-ups is far closer to that of a petrol or diesel car, zero tailpipe emissions.

Against: Infrastructure is in its infancy; high CO2 emissions from current production process; technology is very expensive.

Toyota Mirai front

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