Where you charge beats what you drive

Home off-peak to public rapid is roughly a <b>tenfold</b> difference in price per kWh. No two mainstream EVs differ in efficiency by even twofold — so the socket sets your running cost, not the car.

Why it works

At UK off-peak rates an efficient EV runs at about <b>2p a mile</b>; the same car on public rapids costs about <b>22p</b>, against roughly <b>15p</b> for a 45 mpg petrol car. Charging exclusively on rapids can cost more per mile than petrol, which is the opposite of what people expect when they buy one. You also pay for the energy that never arrives: the meter counts what the charger draws, and about 12% of it is lost on home AC charging.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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How much does it cost to charge an electric car?

Home off-peak to public rapid is roughly a <b>tenfold</b> difference in price per kWh. No two mainstream EVs differ in efficiency by even twofold — so the socket sets your running cost, not the car. At UK off-peak rates an efficient EV runs at about <b>2p a mile</b>; the same car on public rapids costs about <b>22p</b>, against roughly <b>15p</b> for a 45 mpg petrol car.

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