Frequently Asked Questions About Electric Cars, Answered

Electric cars (EVs) are still quite new and so there are still a lot of misconceptions about them. Many drivers are unsure about making the switch, mainly because they have questions and concerns about owning and driving an EV.

 

Many are concerned about moving away from petrol or diesel cars (ICEs) and taking a step into the unknown.

 

We're here to address those fears and give you the confidence to plug into the revolution.

 

If you're worried about owning an electric car, these FAQs are here to help. We've answered your pressing concerns to help you take the first step along the path of EV ownership.

 

Why Do Electric Cars Have Green Number Plates?

Green number plates help other drivers or local authorities identify zero-emission vehicles. This helps "local authorities design and put in place new policies to incentivise people to own and drive (electric cars)”, according to the UK Government.

 

As of February 2025, green number plates are only cosmetic. There are currently no such schemes running in the UK. That means that green number plates are currently just a way of showing off that you drive an electric car.

 

However, it has become the norm for dealers to fit green number plates to new models in preparation for these schemes.

 

If you wish to fit green number plates onto your older electric car, they cost about £40 for a pair. Check the UK Government website for more advice about changing your licence plates.

 

What Does an Electric Car Engine Look Like?

The diagram on the left shows under the bonnet of a standard ICE & the diagram on the right shows under the bonnet of a 2018 Nissan Leaf (40kWh).

As you can see, electric cars and ICEs look very different under the bonnet. As well as the electric motor and battery pack sitting where the cylinder block should be, an EV also has fewer fluids (oil, coolant etc) and doesn't have a fuel tank, line, or pump.

 

How Many Moving Parts Does an Electric Car Have?

An electric car engine only has around 20 moving parts. In comparison, a standard ICE engine will have just under 2,000.

 

To highlight this point even further, a Tesla’s drivetrain has just 17 moving parts. In comparison, an ICE drivetrain has over 200 moving parts.

 

What Type of Battery Does an Electric Car Use?

Electric cars use lithium-ion batteries. These are the same type of rechargeable batteries used in smartphones and tablets. However, those used in an electric car have a much higher power output and an extended lifespan.

 

How Big is an Electric Car Battery?

Electric car batteries range in size and are measured in kilowatt-hours (kWh). A kilowatt-hour is a measure of how much energy you will use in 1 hour of constant use. For example, a 1kWh appliance will use 1 kW of energy every hour it is in use.

 

Electric car batteries are much more powerful than this. One of the smallest electric car batteries are 17.6 kWh (fitted to the Smart fortwo). Even this is small compared to the standard battery size. Most range from around 30 kWh all the way up to the largest at 100 kWh+.

 

What Voltage is an Electric Car Battery?

Most electric car batteries have a voltage between 400 and 800V. Some high-end models have an even higher voltage.

 

Electric cars also have a standard 12V battery to power the electronics, windscreen wipers and in-car infotainment.

 

Do I Own the Battery in an Electric Car?

While you can still lease an electric car battery, most are now included in the purchase price of an EV.

 

In the early days of electric cars, some manufacturers would lease the battery separately, even if you bought the car outright. This was a massive disadvantage for customers as it included mileage caps and extra leasing costs.

 

However, it was seen as necessary while the technology was still developing. Now, electric car batteries last long enough that mileage caps aren't needed.

 

Leasing a battery means more monthly payments on top of PCP (Personal Contract Purchase) or PCH (Personal Contract Hire) Finance payments.

 

How Much Electricity Does an Electric Car Use?

The average electric car uses 0.2 kWh (kilowatt-hour) per km (0.3kWh per mile).

 

This means that it would take 150km (93 miles) to completely drain a 30kWh battery and 500km (311 miles) to use all the electricity in a 100kWh battery.

 

However, these figures don't consider regenerative braking which extends the range of electric cars. It captures otherwise wasted kinetic energy and stores it in the batteries for you to use later.

 

Do Electric Cars Lose Charge When Parked?

Electric cars only lose minimal charge when parked. However, this can quickly add up over time.

 

If you plan to leave your electric car parked for any length of time, make sure to charge the battery to between 50% and 80% first.

 

You should also put it in “Deep Sleep” or “Power Save” mode. This will shut down any unnecessary systems and conserve energy better during a period of inactivity.

 

How Long Can an Electric Car Sit Without Charging?

The high voltage battery which powers an electric car can survive up to 6 months of inactivity, as long as it has more than 10% charge.

 

The 12V battery in charge of the car’s electrics will drain much faster, just like those in ICEs. You could expect to see this go flat in a couple of months if you don't use the car at all.

 

How Does the Heater Work in an Electric Car?

Electric cars don’t heat the cabin by using wasted heat energy from the engine as an ICE does. Electric motors are too efficient and don't produce enough heat to use in this way.

 

Instead, an EV uses a heat pump system. This works much like an air conditioning system.

 

A heat pump takes heat energy from the outside air and compresses it. This compressed air is kept warm as it travels through the system and is then released into the cabin.

 

As heat pumps are very efficient, this is a much more sustainable and eco-friendly way of heating a car. The most efficient can generate over 4kW (kilowatts) of heat energy for every kW of electrical energy used. They also barely waste any energy.

 

How Much Road Tax Does an Electric Car Pay?

Electric cars do not pay road tax during their lifetime. In 2017, the UK Government changed the road tax bands to penalise high-polluting cars. As such, road tax is calculated based on your exhaust emissions.

 

Electric cars produce zero exhaust emissions, so are exempt from both first year and standard rate payments.

 

Do Electric Cars Need MOTs and Servicing?

Even though an electric car works very differently from an ICE vehicle, they still need to be looked after with regular maintenance. If your electric car is older than three years old it will need a yearly MOT.

 

It is important to keep up with yearly servicing to ensure that your EV is in its best condition. You can use BookMyGarage to compare electric car services in your local area and save money.

 

Read More

Do Electric Cars Have Gears?

Electric cars don't use gears like an ICE. Find out why they don't need them and what sort of transmission they use instead in this article.

 

When Will All Cars Be Electric in the UK?

Electric cars are rapidly growing in popularity, but they are still far from the norm in the UK. However, that will change very soon. Find out more about when all cars will be electric in this article.

 

How Many Electric Cars are There in the UK?

As more and more drivers make the switch to electric cars, the number of EVs on UK roads are growing every month. Learn more about the popularity of electric cars in the UK in 2022 and find out the latest stats and figures in this article.

 

Is an Electric Car Right for Me?

Now that you feel a bit more secure about the prospect of owning an electric car, it's time to work out whether driving one would still meet your needs. Find out what you should consider when deciding if an EV is right for you in this article.

 

What is an Electric Car?

An electric car is a zero-emissions vehicle that works in a totally different way to a petrol or diesel car. Learn more about what an EV is in this guide.

 

Do Electric Cars Need an MOT?

Whilst they may be made up of fewer parts than a petrol or diesel car, electric vehicles need to be MOT tested every year once they are three years old. This article can tell you about the slight differences between an electric car MOT and a traditional petrol or diesel car MOT.

 

Do Electric Cars Have an Exhaust?

As electric cars do not produce any emissions, there is no need for them to be fitted with exhausts. This article can tell you why the lack of an exhaust on an electric car is beneficial.