Charging costs for your electric car are simple to calculate. Here’s how to solve it
There are many reasons to go electric: for one thing, those pesky CO2 things. But there’s another incentive to make the switch besides doing your bit for polar bears: the charging costs of electric cars.
You see, charging an electric car has, at least historically, been cheaper than filling it with conventional fuel. And that means that over the course of owning an electric vehicle, you could save a lot of money in running costs. really
Of course, there are a couple of important caveats: For the numbers to work, you’ll need to do most of the loading at home. This is where electricity is most affordable (even with rising energy costs) and some tariffs will allow you to make the most of cheaper night-time rates when demand is low.
Public charging points, including the so-called “fast” chargers that appear at motorway service stations, tend to be much more expensive. And while they’re a boon for quickly recharging on a long trip, you’ll pay for the privilege. So much so that the price per driving mile might not be that different from a petrol or diesel car. Boo! Whistle!
It also depends on how much driving you do. If you’re only venturing to the shops every now and then, or making a short, irregular commute (hello working from home), then the benefits of an electric car will be much more subtle.
But if you drive a reasonable distance each year and can plug your electric car into a wall box in your driveway or garage, you’re onto a winner. Now it’s just a matter of figuring out exactly what the costs are. Please keep scrolling…
How do I calculate electric car charging costs?
It’s pretty easy to find out how much it costs you to charge. You just need to know the size of the battery, the range of the car and the unit price of electricity per kilowatt-hour (kWh).
For argument’s sake, let’s use the Kia Niro EV as an example: the latest version of it comes with a 64.8kWh battery and, on paper, can go 285 miles on a full charge.
Also for argument’s sake, let’s say you’re charging at home and you’re paying 34 cents per kilowatt-hour for electricity. It is based on the capped average unit price set from October 2022 through March 2023, although it varies slightly by region.
That means a full charge of the Niro EV from the point will cost you 64.8 times £0.34, which is… a cut of over £22. Sounds pretty tempting when the average price of a tank of fuel peaked at over £100 in June 2022.
We must remember that the autonomy of the Niro EV is 285 miles according to official laboratory tests. In actual driving, you’ll see less than this, but so does the “official” fuel economy of a gas or diesel car. More on that in a moment.
Anyway, 285 miles from 64.8 kWh gives us… about 4.4 miles per kilowatt-hour (mi/kWh, or sometimes mipkWh). This unit is basically mpg for electric cars, and 4.4 is pretty good. The most efficient EVs will exceed 5.0 in the summer, while the least efficient will struggle to exceed 2.0. Eep.
OK, last piece of the puzzle: if you get 4.4 miles/kWh and you’ve paid £0.34 for that energy, your running cost per mile is… less than eight pence. £0.077 to be exact.
How much cheaper is electricity than petrol or diesel?
Okay, now let’s look at how this compares to internal combustion. And we can use the Niro again here, because there is also a petrol version of this car. And yes, before I mention it, the latest petrol Niro is hybrid as standard, but there’s no plug-in and all the power that powers this car ultimately comes from the fuel tank (42 litres, if you you ask).
On paper, the Niro can get 64.2mpg and, according to the RAC, the average price of unleaded in the UK at the time of writing is 148.74p. There are 4.546 liters in a gallon, so a gallon costs around £6.76.
All we have to do is divide 64.2 mpg by the price of a gallon and we get running costs per mile of… 9.63 pence. Which means it’s almost two cents per mile cheaper to drive the EV.
I’ll be honest, I thought the savings would be… bigger.
You are right to feel a little aggrieved. A couple of years ago, domestic electricity cost around 13-14p/kWh, so almost tripled, and could rise further when the government cap on unit price ends. The steep rise has wiped out a large chunk of the savings EV drivers were making on their running costs, and there’s no telling when things will calm down again.
The thing to remember is that fuel prices have also been volatile – it wasn’t long ago that fuel was up £2 a liter as Russia’s invasion of Ukraine, a weak pound against the dollar and supply problems raise the price At that time, electric vehicle drivers could feel quite satisfied; less now
It looks like energy prices, whether for electricity or fuel at the pumps, will continue to fluctuate over the next year or two, so sometimes the electricity savings will be big and sometimes not they will be After that, we hope to have a better idea of the long-term trend.
But previously the running costs of electric vehicles were around a third, and sometimes a quarter, of their combustion engine equivalents, making the case for ownership much stronger as prices purchase prices for electric vehicles tended to be thousands of pounds higher. The higher the electricity costs, the longer it will take you to recoup that difference.
How much does it cost to collect in public?
This depends on the charging provider you use. Tesla drivers using the company’s Supercharger network currently pay a maximum rate of 67p/kWh, although drivers of other brands must pay 77p. Ionity fast chargers will set you back 69p/kWh; Chargemaster/bp pulse chargers start from 65p/kWh for non-member pay-as-you-go customers.
In other words, charging in public is probably twice as expensive as charging at home. So if you don’t have your own home charging unit installed and need to rely on third-party chargers, it won’t be any cheaper. At least, not for now.
