Working out what it costs to charge an EV at home only takes three numbers: the size of the battery, how much of it you are filling, and your electricity price.
The formula
Cost = energy added (kWh) ÷ charging efficiency × price per kWh.
Charging is not 100% efficient. Between the wall and the battery, roughly 8–12% of energy is lost as heat, so the energy you pay for is a little higher than the energy stored.
Example
Charging a 60 kWh battery from 20% to 80% adds 36 kWh. With 10% losses you draw about 40 kWh from the grid. At 0.15 per kWh that is around 6.00 for the session.
Ways to pay less
- Use an off-peak or EV-specific tariff and charge overnight.
- Charge to 80% for daily use; it is faster and gentler on the battery.
- Charge from solar if you have panels (see our solar EV calculator).
Try the EV charging cost calculator with your own tariff to see the exact figure.