Electric car charging guide
How to charge an electric car
By Adrian Porter
Article 1 of 1
All you need to know about charging an electric car, including how much it will cost you to charge and how you can reduce this cost
Unlike traditional fuel cars, which can be filled with petrol or diesel in minutes, electric cars can take a long while to charge – especially if you’re planning to recharge using a typical three-pin plug (don’t do this).
Out on the road, the electric car charging infrastructure is growing quickly. But with so many different major and local networks, a large number of different adaptors and various power levels, you’d be forgiven for thinking it’s all a confusing hassle.
Happily, it’s not as complicated as it sounds. And there are many good reasons to buy an electric car, such as not costing as much to run as an equivalent petrol or diesel car. Plus they are nippy, silent and incredibly satisfying to drive.
To help make it all simple, we’ll explain:
Charging at home
- How much does it cost to run an electric car?
- Can I plug my electric car into a regular three-pin socket?
- Choosing the best wallbox charger
- Single vs three-phase networks
- Do I need a smart charger?
- Save up to £500 with the wallbox grant
- Vehicle to grid charging
Are you considering an electric car? Here are the best electric cars we've tested.
How much does it cost to run an electric car?
If you’re charging exclusively at home, our research shows that an electric car could add between £450 and £730 to your annual electricity bills.
However, you will save money on fuel, compared with the cost of running a traditional car. When we compared the cost of charging a Nissan Leaf to the average cost of fuelling equivalent-sized petrol and diesel cars, over 10,000 miles we found the Leaf was £308 cheaper than an equivalent diesel car - and £609 cheaper than an equivalent petrol car.
Annual fuel cost: latest Nissan Leaf vs a medium-sized petrol and diesel car
Nobody tests cars as thoroughly as we do. Don't buy a new car until you've read our expert Which? new and used car reviews.
Charging at home: can I plug my electric car into a regular socket?
Yes, you can - but you won't want to. Charging your electric car at home (and possibly work) makes owning an electric car far more convenient, but use a regular three-pin wall socket and you're looking at very, very long charging times - in excess of 25 hours, depending on the car.
Unlike the picture above, what you're going to need to make charging at home easy and convenient is dedicated parking (such as a driveway) with a power supply, and a wall charging unit.
Here are the steps to charging your electric car at home.
Get a wallbox charger
Electric vehicle wall charging units (also called wallboxes) are available in different forms and powers. They will drastically reduce charging time compared with a regular three-pin plug.
Official charging times: plug vs wallbox charger
To get the best wall charging unit for you, you’ll need to make a number of decisions:
- Tethered or untethered
- Type of plug
- Rate of power
- Smart or not
Untethered or tethered charger?
- Untethered: No attached charging lead. More hassle every time you want to plug in, but allows you to swap out the lead - such as from Type 1 to Type 2. Some consider it future proofing.
- Tethered: The charging unit has a power lead attached to it. It’s convenient as it means you can just pull up and plug in, as opposed to retrieving your car’s charging lead from the boot.
Are all electric car chargers the same?
These are two different kinds of connectors for charging an electric car at home (there are more for public charging). And several different speed (power) options.
Starting with the connector, your electric car will be able to take either a Type 1 or Type 2 connector. The difference is the shape of the plug, it does not affect the rate at which it can charge your car.
In recent years, cars with a type 2 charging socket are much more common. Make sure you know which type of connector your car is compatible with before ordering your wallbox.
Don't settle for second best. Make sure your next car is a Which? Best Buy car.
What wattage wall charger should I buy?
This is perhaps the most crucial bit. There is no single power option. Your typical choice is up to 7.4kW for a typical UK home.
To save money on the charger, you could choose a lower power rate (such as 3.6kW). Though it will take longer to charge your car.
It is possible to have an even faster charger, up to 22kW. If your car is capable of receiving a charge like this (and many are not) it will cut down charging rates again.
Official charging times for the Tesla Model X (100kWh)
The only problem is that speedier charging rates require a three-phase connection, which you may not have in your home.
Can you speed up charging? The difference between a single phase and a three-phase supply
Your electricity is supplied through either:
- a single phase network that, simply put, has one live wire
- or a three-phase network that has three live wires. You can connect to all three for a faster power supply.
The good news is that the majority of the UK is served by a three-phase network.
The bad news is that most UK dwellings are attached to only one of those three live wires. So in fact, most homes have a single-phase connection, despite it being a three-phase network.
Most homes have a single-phase connection, despite it being a three-phase network
How to check if you have a three-phase connection
According to UK Power Networks (the organisation that maintains our electricity networks), the way to check your own connection is to look at your fuse box.
- One 100 amp fuse means you have a single-phase connection
- Three such fuses means a three-phase connection.
As the three-phase network is widespread across the UK, it does open up the possibility of upgrading your single-phase connection to a three-phase connection.
If you want a higher rate of power, find out if it’s possible to upgrade by speaking to your energy supplier.
Do I need a smart charger?
Smart chargers are charge points that can be accessed remotely. This will usually work via an app on your smartphone, allowing you choose when your car charges, and how much energy you've used.
This could be particularly useful if you have a time-of-use tariff, such as Economy 7, when the cost of electricity is cheaper during the night. So you could set your charger to charge your electric car during those cheaper hours.
However, this is offset by smart chargers being more expensive than regular chargers.
As of July 2019, the wallbox grant (explained below) will only apply if the wallbox you are buying has smart functionality.
Save up to £500 with the wallbox grant
Through the Electric Vehicle Homecharge Scheme, the UK government currently offers a grant toward buying and installing a wallbox. The grant covers 75% of the cost, up to a maximum of £500.
This grant is separate to the Plug-in Car Grant (PICG), which reduces the cost of buying an electric car.
In order to get the wallbox grant, the wall charging unit has to be installed by a supplier approved by the Office for Low Emission Vehicles (OLEV). They will be able to claim for the grant on your behalf.
You also have to meet these conditions:
- You must be the owner, lease holder or have an electric car on order.
- Your plug-in vehicle was purchased after 1 October 2016.
- You have not already claimed the grant for your vehicle.
- As of July 2019, the wallbox charger must have smart functionality
Other criteria includes:
- The date of installation must not be more than four months ahead of the delivery date for your car, or the start date of its use.
- The scheme is limited to one installation at a domestic residence per eligible vehicle, up to a maximum of two charging units at one residence. So if you want to claim for two charging units, you must have two electric vehicles (vehicles can includes cars, vans or taxis - check gov.uk to find a full list of eligible vehicles).
Vehicle to grid (V2G)
Vehicle to grid technology is an advanced form of power management, and it's a potentially crucial part of the electric car future.
Energy supplier Ovo Energy is currently running a vehicle to grid trial (which is still open to registrations for Ovo customers). If you're registered to the trial, you get to choose a charging schedule via an app on your phone. This sets the minimum state of charge you need your car to be and for what time.
For example, you’ve come home at 6pm in the evening, plugged your car in and specified that you want your car to be at least 80% full by 7am the following morning.
Overnight, your car will be charged when demand on the network is low, and when it’s more likely that energy from renewable sources is feeding the grid.
But when demand on the grid is high, the charger can take power from your car, power your home and sell any excess energy back to the grid, helping to manage the UK power network and earning you money. Your app will tell you how much money you’ve made by doing this.
The trial will run for two years. Ovo Energy estimates people could save up to £305 on energy bills. According to our own calculations, this will cover the majority of running costs for an electric car.
In the future, we expect to see more vehicle to grid chargers and schemes. Especially following the closure in April 2019 of the government’s feed-in-tariff - this paid you for generating your own renewable electricity.
Electric cars and public charging
Charging out on the open road may be the source of some people’s ‘range-anxiety’ – which means fear of running out of juice. But ironically, it's public rapid chargers that offer the fastest way to top up your batteries. Some cars can reach 80% charged in 40 minutes or less.
Plan accordingly and it’s quite possible to do long journeys thanks to the sprawling and growing network of charge points.
Public charging point speeds explained
These charging points can be divided into three main categories: Slow, fast and rapid chargers.
- Slow chargers offer power up to 3kW
- Fast chargers offer speeds between 7kW-22kW
- Rapid chargers are above that, with speeds between up to 43kW or 50kW
- Tesla’s own supercharger network, exclusive to its own cars, can charge up to 120kW.
There are several different types of connectors. Your car will be designed to work with 2-3 of these directly, but not all. Adaptors are also available.
Three-pin plug: Not just found at home, there are three-pin chargers out there in the wild. These offer slow charging speeds (3kW). If you’re running low, it’s worth avoiding these in lieu of faster charging options wherever possible.
Commando: You’re probably familiar with these types of plug if you’re a boater or tow a caravan. Commando plugs can supply power between 3-22kW.
Type 1: Can supply power between 3-22kW.
Type 2: Common connector type and a range of power rates available, from 3kw (slow), 7-22kW (fast) and some up to 43kW (rapid).
According to Zap-Map (who provide a free and great interactive map of chargers around the UK ), there are nearly 20,000 public charging connectors in the UK, over 4,000 of which are rapid chargers.
If your car is capable of being charged via a rapid charger (and writing in 2018, most new electric cars are), you can charge your electric car from near empty to around 80% full in 30-40 minutes, or up to an hour in some cases. It is much quicker than charging at home.
CCS: A connector type for rapid charging only, able to supply 50kW of DC (all above connector types supply AC).
CHAdeMO: Just like the CCS, it supplies 50kW of DC power straight to your car.
Superchargers (Type 2): The fastest on the market and exclusive to Tesla, can supply a whopping 120kW.
It’s not just the variation in speeds and connector types that make charging your car complicated. More of an issue is the large number of networks that cover the UK.
PodPoint, Polar, Ecotricity are among the biggest, but there are more than 20 networks across the UK. Many operate a pay-as-you-go services, but before you can use the charger you’re typically going to need to download an app to connect to it, or order an applicable RFID card or key fob which you can also use to connect to your account with that network.
- Polar (who claims to be the largest network in the UK), use both a pay-as-you-go model and a subscription service. Members who pay a subscription get free access to the majority of charge points across the UK, and preferential rates at the rest.
- Instavolt is an unusual charging network that does not require any sort of sign up, but charges your card directly, similar to a regular fuel station.
- Charge Your Car (CYC) is a network of EV charge points all over the UK. This includes Energise, GMEV, Source West and ChargePlace Scotland. Polar members also have access to the CYC network.
With so many networks operating across the UK alone, if you’re travelling long distances you’re going to need an array of apps, potentially an RFID car of fob for your chosen/most convenient network, and get in the habit of planning ahead to see what charging points are on your journey and you need to sign up to.
The lack of a completely universal system is the perhaps one of the biggest pains of driving your electric car, assuming you frequently cover long distances.
But this looks set to change. Nine suppliers have pledged to open their networks to each other's members through a roaming partnership by the end of 2019.
When implemented, the agreement will mean EV drivers in the UK only require a single subscription to access public charging stations operated by any of the signatories. The operators will also share charging station information so drivers can get information about chargers and costs.
The pledge has been signed by Allego, EV Box, New Motion, Chargemap, ChargePoint, Charge4europe, Engenie, Franklin Energy and Travelcard.
The government has also set out that it wants to see all newly-installed rapid and higher-powered chargepoints provide debit or credit card payment by spring 2020. This should also help eliminate the need for multiple apps or membership cards.
If an electric car isn't right for you just yet, take a look at our expert pick of the best hybrid cars.