How Much Does It Cost to Charge an Electric Car?

So you are thinking of switching to an EV, one of the first questions you’ll ask is:
how much does it cost to charge an electric car?

The answer depends on three main factors:

  1. Your car’s battery size

  2. Its real-world efficiency (miles per kWh)

  3. The electricity tariff you use

Understanding these elements – and how peak and off-peak pricing works – is key to keeping your EV running costs as low as possible.

Standard EV Battery Sizes

Electric vehicles come with a range of battery capacities, typically measured in kilowatt-hours (kWh). Here are some common examples:

  • Small battery EVs: 35–45 kWh

  • Medium battery EVs: 50–65 kWh

  • Large battery EVs: 70–100+ kWh

Real-world examples include:

  • Nissan Leaf – 40 kWh battery

  • Tesla Model 3 – ~60 kWh battery

  • Tesla Model Y – ~75 kWh battery

  • Hyundai Kona Electric – 64 kWh battery

  • Kia EV6 – 77.4 kWh battery

  • BYD Atto 3 – 60.5 kWh battery

  • Volkswagen ID.4 – 77 kWh battery

As a simple rule: the larger the battery, the more it costs to charge from empty to full. However, larger batteries often provide more miles per charge.

Miles Per kWh: Real-World Efficiency

An EV’s efficiency is measured in miles per kWh. In real UK driving conditions, most EVs achieve:

  • 3.0–4.5 miles per kWh

For example:

  • A 40 kWh EV achieving 4 miles per kWh = 160 miles of range

  • A 60 kWh EV achieving 3.5 miles per kWh = 210 miles of range

  • A 77 kWh EV achieving 3.2 miles per kWh = 246 miles of range

Driving style, temperature, and motorway use all impact efficiency. Winter driving typically reduces range by 10–20%.

So, How Much Does It Cost to Charge an Electric Car at Home?

Let’s look at typical UK electricity prices.

Standard Tariff Example

If your electricity costs 28p per kWh (typical standard variable tariff):

  • 40 kWh battery = £11.20 (0.28 × 40)

  • 60 kWh battery = £16.80

  • 75 kWh battery = £21.00

  • 77 kWh battery = £21.56

If your car achieves 3.5 miles per kWh, your cost per mile is:

28p ÷ 3.5 = 8p per mile

That’s already significantly cheaper than petrol or diesel.

EV Tariffs: Lower Overnight Costs

Many suppliers now offer EV-specific tariffs with cheaper overnight rates.

For example:

  • Off-peak rate: 7–10p per kWh

  • Peak rate: 35–45p per kWh

If you charge a 60 kWh EV at 8p per kWh overnight:

  • 60 × £0.08 = £4.80 for a full charge

  • Cost per mile (3.5 mi/kWh) = just over 2p per mile

That’s exceptionally low running costs.

The Hidden Issue: Higher Peak Rates

While EV tariffs offer attractive overnight rates, they often come with higher peak-time electricity costs.

For example:

  • Standard tariff: 28p all day

  • EV tariff: 8p overnight, 40p peak

If you only charge overnight, this works well.

However, if you use most of your household electricity during peak hours (cooking, washing, heating, etc.), your overall bill may increase.

The key question becomes:

Do peak-time increases offset the savings from cheap overnight EV charging?

For some households, the answer can be yes — especially if daytime electricity usage is high.

Shifting Appliances to Off-Peak

One way to maximise savings is to run appliances overnight, such as:

  • Dishwashers

  • Washing machines

  • Tumble dryers

Modern appliances often have delay timers, making this relatively easy.

By shifting more usage into the cheaper window, you improve the value of an EV tariff. However, not everyone wants to reorganise their daily routine around energy pricing.

The Smart Solution: Battery Storage

This is where home battery storage transforms the economics.

With a home battery system, you can:

  • Charge your battery at cheap overnight rates

  • Use that stored energy throughout the day

  • Avoid buying electricity at expensive peak rates

  • Charge your EV at the lowest possible cost

Instead of changing your lifestyle, your energy system does the work for you.

Battery storage allows you to:

  • Shift all household consumption to off-peak rates

  • Protect yourself from high peak pricing

  • Reduce reliance on the grid during expensive periods

  • Lock in consistently low EV running costs

For households with higher daytime consumption, battery storage often delivers the strongest long-term savings.

Final Answer: How Much Does It Cost to Charge an Electric Car?

In the UK:

  • On a standard tariff: £11–£22 for a full charge, roughly 7–9p per mile

  • On a good EV overnight tariff: £4–£7 for a full charge, as low as 2–3p per mile

  • With battery storage optimisation, potentially the lowest possible long-term cost, without lifestyle compromise

The true cost depends not just on your car, but on how intelligently your home energy is managed.

At ESME, we help homeowners design smarter energy systems that maximise savings, so your electric car really is as cheap to run as it should be.

Want to calculate your savings? Just enter your postcode below. No need to give us any details if you don’t want to either. Have a look and see for yourself, and if you do want some help or advice on tariffs and storage, we would love to help.


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Maximising Off-Peak Energy Savings with Home Battery Storage