Electric cars seem to offer a good way to reducing pollution levels in towns as they don't use fossil fuels directly. They also offer a way to reduce the UK's overall energy use for transport as they are more efficient than traditional combustion engines.
However, at the moment in the UK, we still rely on fossil fuels to generate electricity in our power stations, so the pollution isn't removed completely - it's just moved away from towns to the power stations.
And, if all car owners in the UK bought an electric car, there would be very negative consequences for the UK’s electricity supply.
In this website we set out the problem and the consequences if nothing changes.
We also offer a number of web-links so that you can follow up on the science in more detail.
Keep on scrolling to find out more
The Leaf has two battery options: a 24 kWh battery giving a range of 124 miles while a 30 kWh battery extends this to 155 miles
This typically takes 3 - 4 hours to charge using a 8 kW (32 amp) Pod Point which has to be wired directly into your house's Consumer Unit like a power shower unit.
People who don't have off road parking can't use this system as it's illegal to trail electric cables across the pavement. These EV owners will have to wait until charging points are fitted at parking points at the roadside or in nearby car parks. But of course you have to wait for the owner of the parked car to return to move their car before you can charge yours - and that might be hours!
That's not the only problem:
An owner said: “When I plugged in the 13-amp cable that comes with the Leaf I discovered that the POD Point was tripping the circuit breakers in the house when it was connected to the car and needed to be manually overridden.”
A Cayenne S E-Hybrid can be fully charged typically in about 2.7 hours – but this needs to be connected to an industrial electrical outlet that can deliver 24 kW – which means a current of over 90 amps - far more than your house can provide!
A normal household supply is limited, and could not provide very high levels of current to fast charge a car. Owners of fast charging cars will have to pay to have a specialised high power supply wired to their house if they want to fast charge their car while they are at home.
On a full charge, the Audi Q6 e-tron quattro's 95kWh battery is claimed to provide you with with a range of over 311 miles
Its combined AC/DC charging system operating at 150kW can store enough energy for a range of up to 249 miles in around 30 minutes charging. But this needs a current of over 500amps! Owners certainly can't rapid charge this car while it's parked in the road unless very specialised charging points are installed and the local electricity network would need to be rewired to make it more robust!
To get ‘fast charging’ (less than half an hour for 80% charge) requires higher currents than are possible from a household supply.
The UK National Grid was not designed to provide these high currents in residential areas - it provides a local network to domestic users which was designed to provide lower currents (mainly for safety reasons).
Trying to pass very high currents through local networks could be very damaging for the materials in the system (cables, transformers etc). The electricity grid will need to be upgraded and made more robust if the UK wants to have more EV's on the road - and this costs money and will require all the roads in the country to be dug up to lay new cables!