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How much does it cost to charge an electric car? EV running costs explained

Published: 20 June 2019

► How much to charge an electric car
► The real-world costs of owning an EV

► We use a Renault Zoe as a case-study

There are several benefits to owning an electric car in 2019; along with environmental brownie points, electric vehicles (EVs) still get government tax grants, and are also exempt from congestion charges in some cities. However, one of the most obvious – but often unquantified – benefits of owning an EV is the low running costs.

We’ll say it now: an electric vehicle will cost potentially far less than a diesel or petrol equivalent given the same use - and you'll maybe never have to visit a petrol station forecourt ever again. But how much cheaper are EVs? Keep reading to find out.

Further electric reading

How to calculate running costs for an electric vehicle (EV)

Every electric car comes with a different-sized battery. The capacity of a battery is usually expressed in kilowatt hours (kWh), a measure of the energy storage available in the cells. A big-batteried Tesla has 100kWh for a very long range, whereas the latest Nissan Leaf comes with a 62kWh power pack. So to calculate how much it costs to charge your car, simply look at the cost of electricity (either your home supply or at a public charging point) and do the maths.

In simple terms, the maths is: Size of battery (kWh) x Electricity cost of your supplier (pence per kilowatt hour) = Cost to charge an electric car. 

Don't worry if you've never done this before. In this handy explainer, we'll show you how to crunch the numbers yourself.

Let’s consider a 100kWh Tesla Model S. A typical public rapid charging point in the UK currently charges around 35p per kWh, so the cost is 100 x 35p = £35 if you were to theoretically charge from completely empty to full. Switch to a cheaper home supply, which could cost 12p per kWh on a good-value overnight tariff, and the maths works out at a more palatable 100 x 12p = £12. That’s a major saving over the cost of a £70-£100 petrol/diesel tankful for a typical executive car.

We live with a Tesla Model S: check out our long-term test here

Real-world case studies: how much does it cost to charge an electric car?

Just like conventionally-powered vehicles, electric cars come in different shapes and sizes, and will therefore have varying costs per mile. For this article, we’ve studied the running costs of a cheap and cheerful Renault Zoe EV run by our sister site Parkers as a long-term test car.

Researchers on Parkers have compared it to the other vehicles on its long-term test fleet, so you can get a better idea of just how much it costs in the real world.

Don’t forget you’ll need to add the initial cost of a home-charging point to these prices, and that’ll set you back around £850 to £1250, including parts and labour. Grants are currently available from the government to subsidise the cost of charger installation.

Running costs of a Renault Zoe EV compared and analysed 

The cost of the Zoe over three months are as follows. We used our colleagues’ 66-mile round-trip journey to work and back as a benchmark, and studied the real-world costs of rival long-term fleet cars for comparison. Before we get into these figures, it’s important to note that these cars are driven by different people with different driving styles, and also that the Leaf’s figures were attained during the winter months; don’t forget that colder weather usually means less efficient batteries.

Renault Zoe cost per mile: 6.1p
Renault Zoe commute cost: £4.03

Compare this with the Parkers’ Nissan Leaf long-term test car.

Nissan Leaf cost per mile: 4p
Nissan Leaf commute cost (est) £2.64

We’ve also compared the same 66-mile journey to the similarly-sized VW Golf GTE plug-in hybrid:

VW Golf GTE cost per mile: 11.5p
VW Golf GTE commute cost: £7.66

Compared to the Parkers’ Toyota C-HR hybrid (non plug-in), you’ll find the following running costs:

Toyota C-HR hybrid cost per mile: 13.4p
Toyota C-HR hybrid commute cost: £8.84

The above suggests that when it comes to hybrids, an electric car is around 50% cheaper. But interestingly, when comparing the running costs of a diesel or petrol car, you’ll find less of a difference.

Parkers’ Citroen C3 is a supermini just like the Zoe, but it’s powered by a 100bhp 1.6-litre turbodiesel engine. Here’s how it compares:

Citroen C3 BlueHDi 100 cost per mile: 10.6p
Citroen C3 BlueHDi 100 commute cost: £7.00

Meanwhile, Parkers’ Suzuki Swift – which is powered by an efficient 90bhp 1.2-litre petrol engine, and driven very efficiently - bears the following costs:

Suzuki Swift 1.2 Dualjet 4x4 cost per mile: 8.7p
Suzuki Swift 1.2 Dualjet 4x4 commute cost: £5.74

How much cheaper does an EV cost per month?

Victory for the Zoe, then. And just to make the advantage clear, multiply those commuting costs by five for a typical working week, and then that by four to get an estimate of the monthly difference, and so forth. It’s advantage electric car all the way...

This is more real-world than a science lab test, and we’ve taken the figures of different drivers for different cars – but the trends are obvious. Don’t forget our running costs only take into account the daily commuting we’ve done; add in extra miles done at weekends and in the evenings, and you’d be saving even more money.

What about public charging of EVs?

Right now, the Parkers’ Renault Zoe only needs to be charged at home each night time owing to its current usage. The cost of charging its battery will appear on your monthly electricity bill.

Home charging is generally cheaper than public charging, so we’ll update this article when we have figures that incorporate that too. However, when you consider 80% of electric car owners charge at home, according to BP Chargemaster, this is the most common scenario for the majority of EV motorists.

In advance of us getting a more comprehensive look at electric car running costs, we’d recommend looking at how much you’d use your EV and calculating how much you’d need to charge up at home versus on the open road. The likelihood is that an electric car will save you hundreds, or maybe even thousands, of pounds a year in cheaper running costs.

Check out more details on what it's like to run an electric car in our links below.

Further electric car reading

The best electric cars and EVs on sale today

The best hybrids, plug-ins and PHEVs

Wireless electric car charging

By Curtis Moldrich

CAR's online editor and racing-sim enthusiast