What it costs to charge an electric car
22 September 2026 · 5 minute read
Less than petrol at home, about the same as petrol at the dearest public chargers, and everything in between. Charging prices are simpler than fuel prices once you know the one unit they are all in, and this guide is that unit, what it means per 100 km, and where the cheap charging is.
Prices are per kWh
Electricity is sold by the kilowatt hour, kWh, the way petrol is sold by the litre. A car's battery holds 40 to 100 kWh, and a car uses 15 to 20 kWh to go 100 km. A charger's price is what one kWh costs there, and a few sites add a per minute fee, a session fee or an idle fee once you are full. ChargeAlong shows the price on a site's page where the network publishes one, and says when it does not.
What that is per 100 km
Multiply the price per kWh by what your car uses per 100 km. A car using 17 kWh per 100 km at a home price costs about the same per 100 km as a petrol car doing 25 km to the litre would, which no petrol car does. The same car at an ultra fast charger, at three to four times the home price, costs about what an efficient petrol car costs. Your car's trip computer shows its kWh per 100 km, and the car guide says what a good figure is.
Home against public
- Home, off peak or solar: the cheapest there is. Running a car this way costs a tenth of petrol.
- Home, standard tariff: a quarter to a third of petrol.
- Public AC posts: often free or near the home price at shops and councils; some car parks charge more.
- Fast and ultra fast chargers: two to four times the home price. Convenience costs, and so does the hardware.
- Roaming and premium sites: the dearest, occasionally above petrol. Worth knowing before you plug in.
Most owners charge at home nine times in ten and fast charge on trips, so the average is close to the home price. See charging at home.
Why fast charging costs more
An ultra fast charger is a large piece of electrical plant on an expensive grid connection, used for a few hours a day, and its owner pays for the peak power it can draw as well as the energy. That cost is spread over the kWh it sells. Sites that are busy all day can charge less; a lonely one on a highway cannot. Faster is dearer, and a 50 kW charger in a town is often the bargain on a route.
Keeping it down
- Leave home full, and charge on the road only what the next leg needs.
- Look at the price on each stop's page before you rely on it, and prefer the network you have a plan with.
- Some networks sell a monthly plan with cheaper kWh. It pays if you fast charge more than a few times a month.
- An AC post at your destination, overnight or while you shop, is often free and always cheap.
- Drive a little slower on the highway. It saves more than any price difference between sites.