How much does it cost to charge an electric car at home?

The size of an electric car’s battery is measured in kiloWatt hours (kWh), and electricity is priced per kiloWatt hour, with rates dependent upon  the contract you have with your energy supplier.

The cost of charging an EV from 0-100% is therefore calculated by multiplying these two things.

For example, an electric car with a 100kWh battery will take 100kWh of electricity to be charged from empty to full. If your energy supplier charges £0.30 per kW of electricity, the car will cost £30 to recharge.

In reality, it isn’t as simple as that, as people don’t let their cars drop to 0%, while car makers recommend charging batteries to 80 or 90% to preserve battery health.

Another way of looking at things is to work out how far your car travels on a kWh. Almost all EVs show average miles per kWh if you fiddle around in the display settings, and a car that manages 4 miles per kWh is more efficient than one that does 2.5 – it’s the electric-car equivalent of miles per gallon. A car that does 4 miles per kWh will cost 7.5 pence per mile in electricity (assuming the notional £0.30 per kWh cost), while one that does 2.5 will cost 12 pence per mile.

Also bear in mind that most EV owners with a home charger have an energy tariff that’s designed for people with electric cars. This may see lower energy prices at night, greatly reducing the cost to charge the car if you schedule its charging sessions via the car’s smartphone app (which most EVs have) or your home charger, if it’s a smart one.