What is an electric car?
There are several different classes of electric vehicle, but arguably the easiest one to remember is the battery electric vehicle (BEV), otherwise known as just an electric car.
In 2017 alone, over 13,500 pure electric vehicles were registered in the UK. At the time of writing, 2018 was set to surpass that figure. In fact, there isn’t a single passenger-car company that isn’t either manufacturing electric vehicles or looking at them for the future.
With the UK Government recently announcing it would ban the sale of diesel and petrol cars by 2040, the industry is slowly moving towards electric vehicles. But what is a battery electric vehicle and, more importantly, how does it work? Read on to find out.
How does an electric vehicle work?
The biggest difference between an electric vehicle and a normal diesel or petrol car is that, in an electric vehicle, the internal-combustion engine has been replaced with an electric motor and a large battery pack.
The car’s drivetrain is now powered by the electric motor instead of an internal-combustion engine. Much like how a regular engine uses diesel or petrol as fuel from the fuel tank, an electric motor consumes electricity that has been stored in a battery pack.
All electric vehicles come with some form of battery pack, often made of lithium-ion stacks. These store electricity obtained from the grid by charging. Much like charging a mobile phone, an electric vehicle is plugged into the grid, through either a home or a public charging unit, to boost its electricity level.
The power from the battery is delivered to the electric motor via its controller, which in turn is connected to the throttle. The amount of throttle movement determines how much power the controller sends to the motor, which then determines how fast the car moves.
Most electric vehicles now also come with regenerative braking. With this, when you release the throttle the car automatically brakes a little. The energy created by the braking is captured and converted into electricity, which is then transmitted to the car’s lithium-ion battery.
Unlike normal cars, electric vehicles do not feature a gearbox with multiple gears. This is because an electric motor delivers its maximum torque immediately, and doesn’t need to be revved. Electric cars also come with a much larger working range for the engine, and thus they don’t need gears to optimise performance and economy.
Advantages of electric vehicles
Electric vehicles have many advantages. The two big ones are much cheaper running costs than internal-combustion cars and zero tailpipe emissions. The first of these comes from the fact that electric vehicles don’t rely on diesel or petrol as their fuel, but on electricity, which is much cheaper.
While a litre of petrol or diesel costs on average £1.30, electricity costs just over 14p per kWh. And although litres and kilowatt-hours aren’t directly comparable, you can compare the cost per mile to see just how efficient an electric vehicle is.
A full 235-mile charge for a Nissan Leaf 40kWh will cost £5.60, meaning the cost per mile of travel is 2.4p. The cost of driving an equivalent diesel car would be around 12p per mile. Over 235 miles, the electric-car owner would save £22.6 over a conventional diesel.
The Government’s Go Ultra Low campaign highlights owners reporting annual savings of over £3,000 in running costs and tax receipts.
The second advantage is the lack of tailpipe emissions. While normal cars emit carbon dioxide, nitrogen dioxide and other harmful pollutants, the tailpipe emissions from electric vehicles is zero. Not only does this improve air quality in busy city centres, but it also means owners of electric vehicles don't pay any vehicle excise duty (VED), or road tax.
Electric vehicles are also exempt from other taxes such as the London Congestion Charge, the recently introduced London T-Charge and the upcoming Ultra Low Emissions Zone payment.
Another point many owners make is that electric vehicles are often more enjoyable and peaceful to drive thanks to their lack of engine noise.
Disadvantages of electric vehicles
One of the big concerns for any potential electric vehicle owner is how far they can drive, or the electric vehicle’s range. Early models had less than 100 miles of real-world range, often inducing a condition known as ‘range anxiety’ in drivers.
While electric vehicles such as the Nissan Leaf come with a lab-tested range of over 200 miles, this is more like 168 miles in real-world driving. That’s still far less than what conventional diesel and petrol cars can achieve.
More expensive models like the Jaguar I-Pace and the Tesla Model S come with 300-mile-plus ranges, but these vehicles cost significantly more than a more conventional electric vehicle such as the Renault ZOE or Nissan Leaf.
Another disadvantage is the charging time. A full charge on a Nissan Leaf 40kWH takes over 13 hours using a 3kW plug. Even with a 50kW rapid charger, it will take over half an hour to charge the car. Conversely, a petrol or a diesel car is far quicker to fill up.
Pros and cons
Whether an electric vehicle is the right car for you is ultimately for you to decide. But it’s worth considering the following few points. What kind of a car do you need? Do you do a lot of driving daily, or is your commute something that could feasibly be covered by an electric vehicle?
Also consider whether or not you have the facilities and space to charge an electric vehicle at home. After all, current estimates show that 90% of all electric vehicles are charged at home. Do you have a garage or a driveway where you can plug in an electric vehicle? Could you install a home wallbox charging unit? These will help speed up the charging.
Owning an electric vehicle can be a very positive experience and improve your motoring life significantly. Just make sure you’re prepared to take the plunge.