Guide to charging an electric car

Slow chargers, fast chargers, and rapid chargers; a guide to charging an electric car

Chris Knapman Murray Scullion
Jul 18, 2018

If you’re in the market for an electric car, one of the major considerations is how you will charge it. If you have off-street parking at home the obvious solution is to plug the car in overnight, taking advantage of cheaper Economy 7 electricity tariffs in the process.

However, you can also find charging points at many workplaces, car parks, motorways services and so on, adding to the convenience of electric vehicle (EV) ownership, as well as making longer journeys possible. 

How long does it take to charge an electric car?

Range anxiety (the fear of running out of battery charge) may be up there as the biggest worry about electric cars for potential owners, but a close second is how long it takes to charge. And the answer is that it really depends on what kind of charger you’re using. But be prepared - all electric cars take substantially longer to charge than it does just to fill up with fuel.

  • Slow chargers (3kW) - typically charge at up to 3.6kW hours, although they are generally referred to as 3kW units. They are most commonly installed at home and can deliver a full charge in about 8-12 hours, although it can be longer for EVs with larger batteries.
  • Fast chargers (7-22kW) - operate at twice the speed of slow chargers. Full charge takes 4-8 hours. Typically costs upwards of £1000, can be bought for home use, but typically found in public places.
  • Rapid chargers (43-50kw and 120kW) - these chargers can give an electric car around 80% battery from empty within 30 minutes. You'll find them at large motorway service stations, but not all electric cars accept rapid charging. Due to the amount of power required, these chargers can't be installed at home.

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How to charge your electric car at home

Charging your electric car at home is the cheapest and easiest option. The good news is that it’s very easy to do, as it’s pretty much the same as plugging in an appliance like a kettle or toaster.

Generally, if you’re charging from home (whether that be on your drive or on the street) you’ll need to use your own cable. Simply plug one end into the car, and the other into the power source, and you’re done. Most electric cars have a separate storage area in the boot to keep the cable too.

You can charge most electric cars using a three-pin plug, but it’s very slow, and will typically take around 8 hours. This is fine for charging your car overnight, but it will grow tiresome having to wait that long all the time.

If you do have off-street parking, it’s worthwhile investing in a dedicated homecharging unit. These typically sit in your driveway, are waterproof, and are wired to your fuse box. They also turn off when your car is fully-charged.

Many manufacturers will supply a wall-mounted slow charger when you buy a new electric car, or if not, there are Government subsidies in place that provide you with £500 off the cost of purchase and installation. Without subsidies, 3kW chargers typically cost between £350-450.

You can also buy fast chargers for your home. They are generally twice as fast as slow chargers, and will take between 4-8 hours to fully charge a car. There’s a price to pay though - as these typically cost around £1,000.

How to charge at electric car charging points

Electric car charging points are spread out around the country. You can find them at motorway service stations, supermarkets, public car parks, work places, and some residential streets in places like London and Birmingham.

These require a little bit more thought in terms of connecting to them. Not only do you need to connect to them, but you need to pay for it too.

Pod Points' charging points require you to supply your own cable, which is no problem. But you need to be signed up to Pod Point. Essentially, you pay for your usage via and app, and also lock, and unlock, your charging point via the same app. It’s intuitive and easy to use, especially for people who regularly use app.

Ecotricity, found at a lot of motorway service stations, uses a similar platform. You communicate with the charging system via an app, and once you’ve paid, you have access. Ecotricity does provide its own cables though.

ChargeMaster is the UK’s largest electric charging network, and runs the POLAR brand which you might see dotted around at charging points. It’s recently been bought by oil brand BP, and will soon help in electrifying BP’s petrol station forecourts. POLAR charges a monthly rate, and then users charge their cars from POLAR branded charging points for free, or very cheaply (around 9p per KWh).

But charging points might be coming closer to your home soon enough. The London boroughs of Richmond, Hounslow, and Westminster have all set up charging points that are adapted from lamp posts. The systems used on these are retrofitted to lamposts, are currently being trialed in attempt to improve air quality in the capital.

Example electric car charging times

Renault Zoe Z.E. 40Nissan Leaf 40kWBMW i3 94Ah
Driving range (real-world approx)150 miles150 miles120 miles
Slow charger13.5 hours16 hours11 hours
Fast charger (7kW)6 hours8 hours4.5 hours
Fast charger (22kW)2 hours8 hours3 hours
Rapid charger to 80 per cent capacity1 hour40-60 minutes35 minutes 

How much does it cost to charge an electric car?

Fuel costs of electric cars are much less than petrol powered vehicles, simply because electricity is cheaper than petrol. However, it’s not that simple.

A typical 7kW homecharger from Chargemaster costs £322, and it’ll charge a Nissan Leaf in around six hours for roughly £5.60 overnight - with enough power to travel around 140 miles. Charging at home, at night, is easily the cheapest way to charge your car.

However, there will be a time when you need to charge on the go, and this gets more expensive. The fastest charging points at motorway service stations may well get you to 80% in around 30 minutes, but they charge a premium. Service stations at peak times might cost you double the price it would cost to charge at home. But Ecotricity for instance, will half this cost if you use them as an energy provider at home.

When comparing an electric BMW i3 with a petrol BMW 318i, the average cost of fuel for the i3 runs at 3.7p per mile, whereas the petrol-powered 318i comes to around 14.2p per mile. Electric cars are also free to tax, while petrol powered ones aren’t. However, insurance on electric cars is generally higher than petrol-powered ones.

In short, the total cost of running an electric car and a petrol powered one are quite similar whren depreciation, insurance, and servicing are taken into account. In total, the BMW i3 comes to 67p per mile, whereas a petrol-powered BMW 318i costs 74p per mile.
Read the full report on how much an electric car costs here

Sign up for public charging

Public charging points are run by a variety of companies, most of which charge for the use of their electricity in the form of a monthly subscription or on a pay-per-use basis. Either way you will need to sign up with the relevant provider to gain access to their charging points, which you then unlock either by swiping a membership card or using a dedicated app.

Unless you plan to visit the same public charging points exclusively, it is worth signing up with two or three providers to ensure you’re covered as and when you need to top up.


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