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How to calculate electric vehicle efficiency

If you’re thinking of making the switch to electric, then you’ll want to make sure you’re getting the most out of your car.

In an electric vehicle (EV), the miles per kWh figure tells you how many miles the car will go on 1 kWh, or unit, of electricity.

So, if your EV has a battery size of 50 kWh and an efficiency rating of three miles per kWh, then on average it can travel 150 miles on a fully charged battery.

How to calculate electric vehicle efficiency

In theory, electric car economy can be calculated by using a car’s battery capacity and its official range.

For example, an electric car with a 40-kWh battery pack and a 100-mile range would have an economy/consumption figure of 2.5 miles/kWh.

How to calculate how much it costs to charge to full capacity via a home charger

To estimate the cost of home charging, you need to apply the following formula: capacity of battery (kWh) multiplied by the price per kW of your electricity supplier, giving you the estimated total cost.

Charging example

A full charge of an entry-level Hyundai IONIQ 5 sporting a 58-kWh battery and an electricity tariff of 22p/kW would be: 58 kWh x 22p = £12.76.

Driving style

Many factors affect the range of an EV, including the capacity of the battery, temperature and the speed the vehicle is travelling.

Electric cars will recharge a little using regenerative braking – this is when you take your foot off the accelerator and the car slows down because the electric motor is now running backwards, which in turn charges the battery.

It’s the most efficient way to drive, but it won’t be able to recharge the battery fully.

Want to learn more?

For those interested or curious about electric vehicles, last year, Arnold Clark opened the Innovation Centre.

The new £5million site opened last year on Dumbarton Road in Glasgow’s West End with the aim of educating visitors about the benefits of alternative fuel vehicles and why they are becoming so important.

There are more than 60 vehicles on site available to test-drive, from plug-in and self-charging hybrids to fully electric vehicles.

You can also learn about the different types of charging and generous government tax and grants available.

We have also recently opened a second Innovation Centre in Stafford, England.

Book an appointment with our business expert at one of our Innovation Centres.

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