Work out the cost to charge your electric car at home or a public charger — by battery size, charge level, tariff and charger speed.
Work out the cost to charge your electric car at home or a public charger — by battery size, charge level, tariff and charger speed. Includes cost per mile and a petrol comparison.
The cost of an EV charge comes down to two things: how much energy you add and what you pay per kWh. Energy added is the battery capacity multiplied by the change in charge level — for example a 60 kWh car charged from 20% to 80% adds about 36 kWh. Because AC charging loses roughly 10% in the charger, cabling and battery, you actually draw around 40 kWh from the grid, and that is what you pay for.
At an off-peak EV tariff of about 7.5p/kWh that charge costs roughly £3.00; at the Ofgem price cap (~24.5p/kWh) it is about £9.80; and on a public rapid charger (45–80p/kWh) the same charge can cost £18–£32. That gap is why overnight home charging on a dedicated EV tariff is so much cheaper than relying on public chargers.
Most EVs return 3–4 miles per kWh, so home charging typically works out at 2–6p per mile — compared with 14–18p per mile for a 45 mpg petrol car at current pump prices. Enter your car’s efficiency and a petrol comparison above to see the saving for your own usage.
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