The cost of using a public charge point can vary by as much as nine times depending when and where the vehicle is recharged, research from the RAC Foundation suggests.

The analysis, available here, shows overnight charging at home can typically be done for as little as 8p per kWh but can be as high as 69p per kWh at a public rapid charge point.

This means that the fuel costs for a 100-mile journey in a 2018 Nissan Leaf could be anywhere between £2.67 and £23.

By comparison – based on official fuel consumption figures – the same journey in a 1.5 litre petrol-engine Ford Focus would cost around £12 in fuel, while a similar Ford Focus with a diesel engine might do it using around £10 of fuel.

The RAC Foundation research comes as What Car? reveals its own analysis. It found that a driver would pay £45.89 to charge an Audi E-tron from 10% to 80% at an Ionity ultra-rapid charger.

However, do the same charge on a domestic charger at an average night-time energy tariff of 7p per kWh and it would cost £4.66.

Using the Ionity charging network makes the E-tron even pricier to run than an equivalent diesel Audi Q7, says What Car?

The E-tron costs 34p per mile, while a Q7 50 TDI, which averages 27.2mpg, costs 22p per mile.

Ionity is one of a small number of extremely fast 350kW charging networks, capable of replenishing an EVs batteries in 30-40 minutes.

However, some slower public charging networks are also far pricier than charging at home, says What Car?

Getting the same battery boost for an E-tron at both a 50kW Shell Recharge point and a 50kW Ecotricity socket costs £25.94, although Ecotricity rates are cheaper for its home energy customers. 

What Car? found that car owners who regularly need to use public charging networks could save money by signing up for a scheme with a one-off or a monthly fee because these often have a lower energy usage rate.

Sign up for a Source London Full plan and it will cost £4 a month, but just £6.32 every time you charge your car up.

Consumers also need to watch out for the hidden costs of using public chargers. Some EV-charger equipped car parks in London charge £9 per hour for parking with no discount for those using the chargers, and What Car?’s research found overstay fees levied by charging networks to discourage that ranged from £10 to £21 per hour.

Steve Gooding, director of the RAC Foundation, said: “Consumers are so sensitive to the cost of filling-up that petrol and diesel prices are routinely displayed to the tenth of a penny.

“Even at the extremes there is unlikely to be more than a 30-40% price differential between the keenest supermarket and the most expensive motorway service area. Not so with electricity. The cost of recharging your battery-powered car can differ dramatically with prices highly dependent on where and when you plug-in, what speed you recharge at and who is operating the facility and providing the power.

“The good news is that overnight charging at domestic rates at home can cost as little as a few pence per kilowatt hour.

“However, contrast that with the dizzying news that you could pay as much as ten times that if you decide to ‘fill up’ at certain ultra-rapid chargepoints on the motorway network.

“The canny consumer is going to have a good deal more homework to make sure their electric car delivers the scale of savings they’re expecting.”

What Car? editor Steve Huntingford added: “Although there are still a lot of slow (3kW) public charging points that are free to use, you’ll have to pay if you want a quick energy fix. And this is where the costs can rack up if you don’t research the various networks in advance.”

What Car? examples of public charging costs for an Audi E-tron

Network

Cost per kWh

10-80% charge

Ionity (350kW)

£0.69

£45.89

Polar Contactless (150kW)

£0.40

£26.60

 

Ecotricity (22kW, 43kW, 50kW)

£0.39

£25.94

Shell Recharge (50kW, 150kW)

£0.39

£25.94

Instavolt (50kW to 125kW)

£0.35

£23.28

Polar Instant (150kW)

£0.35

£23.28

Genie Point (43kW, 50kW)

£0.30

£20.95^

Polar Contactless (43kW, 50kW)

£0.30

£19.95

ESV EV Solutions (43kW, 50kW)

£0.29

£19.29

ESV EV Solutions (43kW, 50kW)

£0.25

£16.63<

Polar Instant (43kW, 50kW)

£0.25

£16.63

Pod Point (43kW, 50kW)

£0.23

£15.30

Charge Your Car*** (43kW, 50kW)

25p per min

£13.85*

Ubitricity (5.5kW)       

£0.20

£13.45>

Polar Plus (150kW)

£0.20

£13.30**

Ecotricity domestic customers

£0.19

£12.64

Polar Plus (43kW, 50kW)

£0.15

£9.98**

Source London Flexi (22kW)

£0.12

£7.91***

Source London Full (22kW)

£0.10

£6.32

^ includes £1.00 fee per charge; < £4.00 monthly fee; *kWh rates vary depending on location; > £9.99 monthly fee, plus £0.15 per charge; ** £7.85 monthly fee; ***£10.00 sign-up fee

To find out how you could save money by running electric vehicles, including our analysis on electric cost per mile, click here

More articles on: