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Electric & Hybrid

EV Charging Time & Cost

How long will it take, what will it cost, and is it really cheaper than petrol? Enter your car and tariff for charge time, charge cost, pence-per-mile and a side-by-side comparison with a petrol or diesel car.

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Estimates and guidance only, based on the figures you enter. Charge time is the theoretical minimum and real-world charging is slower (AC losses, DC tapering above ~80%, cold weather). Running costs depend entirely on your electricity tariff, fuel price and real efficiency. Not financial advice.

How EV charging time is worked out

The baseline is simple: energy to add ÷ charger power. If you add 36 kWh on a 7 kW home charger, that's about 5 hours. This tool works out the energy from your battery size and the charge window (start % to target %), then divides by the charger's power.

Real charging is a little slower than the theoretical figure. AC (home/destination) charging loses roughly 10% to heat and conversion, and rapid DC charging slows sharply above about 80% to protect the battery, which is why public rapid sessions are usually quoted 10 to 80%.

How much it costs to charge

Charge cost is energy added (kWh) × price (p/kWh). The price is where the big differences live: a dedicated overnight EV tariff can be a fraction of the day rate, while public rapid charging is typically the most expensive way to charge.

EV vs petrol: cost per mile

To compare fairly, reduce both to pence per mile:

On typical figures an EV often costs noticeably less per mile, especially on a cheap overnight tariff, though frequent public rapid charging narrows the gap considerably.

What affects real efficiency

Miles per kWh varies with speed, temperature, terrain and driving style. Most EVs sit around 3–4.5 mi/kWh; motorway speeds and cold weather push it down, gentle town driving pushes it up. For the most accurate result, use your own trip computer's lifetime average.

Frequently asked questions

How long does it take to charge an EV?

Energy to add divided by charger power. Adding 36 kWh at 7 kW is about 5 hours; the same on a 50 kW rapid is well under an hour to 80%, after which it slows down.

How do I work out the charge cost?

Energy added (kWh) × electricity price (p/kWh). 36 kWh at 24.5p is about £8.82; on a 7p overnight rate it's about £2.52.

Is an EV cheaper than petrol per mile?

Usually, especially on a low overnight tariff, often a third to a half of petrol's per-mile cost. Public rapid charging narrows the gap.

What miles-per-kWh should I use?

Around 3–4.5 mi/kWh for most EVs. Use your car's own average for the best accuracy.