Charging at home

Using a portable charger

You can charge your vehicle from a normal mains socket, using a portable charger (often called a "granny cable"). These charge at 2.3kW as they only draw 10A and therefore your car will take longer to charge. If your car has a small battery (under 22kWh) then it will still recharge over night on a portable charger, so many owners of small battery EVs just rely on their portable charger for all their charging.

When charging at 2.3kW, you will get you about 9-10 miles per hour of charging.

More recently the use of portable chargers has been discouraged and are now sometimes classed as "occasional use" or "emergency" chargers. This is really to encourage the installation of a wall charging unit, as they are safer in circumstances where the existing mains wiring may not be able to cope with the constant 10A current draw (i,e, when using a spur socket) or misuse, such as using extension leads. Portable chargers are safe to use as long as you use common sense and use them properly.

Portable chargers are very handy for:

  • Hybrid and small battery EV owners who have shorter charging times

  • Charging at home until your new wall charger gets installed

  • EV owners who have a second home or holiday home

  • Charging when away from home, such as visiting family or staying at a guest house

  • Charging at work or when on site

  • Emergency backup if your wall charger breaks

Note: The electrical regulations changed on 1st January 2019 which effects the use of portable chargers. Standard mains sockets may not be able to cope with supplying 10-13 amps constantly, so now there is a new heavy duty mains socket which is labelled as "EV". For further information see here. Therefore, if using a portable charger is your permanent solution, then you should maybe get your socket upgraded by an electrician.

Charging an EV from a terraced house using a portable charger. Just make sure the cable isn't a trip hazard to pedestrians!

Installing a wall charger

Most EV owners get a proper wall charger installed. These have a dedicated feed cable from the consumer unit to allow the vehicle to charge at a higher speed as they can draw up to 32A. Using a wall charger is also safer as you're not reliant on your existing mains wiring and is also slightly more efficient too, saving you money in the long run.

A Government OLEV grant of £350 is available towards the cost of the installation. To qualify for the grant you need to own (new or used) or have regular use of an electric vehicle and have off-street parking. You have to use an OLEV approved installer and they claim the grant on your behalf, so the resulting cost of the installation will typically be around £350-£700, depending on your installation requirements and the model of charging unit.

Since July 2019, the OLEV grant only applies to "smart" chargers. These are chargers where they can be remotely controlled by an app on your phone or by the electricity provider . This means you can use timed cheap rate electricity tariffs, or the grid can load balance at peak times. Because of this, chargers have got more expensive but also there's now more functionality and more models to choose from.

There may be situations where you don't qualify for the OLEV grant. Such as the space where you park your car may technically still by on the public road, yet there isn't a pavement between the parked car and your property. In these circumstances, you just have to pay the full price of the installation. You may also want a basic charger (i.e. not the newer 'smart' chargers) or a model of charger that doesn't qualify for the OLEV grant and you simply have to pay the full installation price. Further options are list below.

Most older EVs will charge at 3.6kW (16A) and newer EVs will charge at 7.3kW (32A). Regardless of the charging rate of your vehicle, it is advisable to install a 32A home charger, as they now cost the same as a 16A version and then are future proof. The car draws the power from the charger, so a 16A vehicle will charge at 16A when connected to a 32A charger.

Charging at 3.6kW (16A) will add about 15-20 miles per hour. Charging at 7.3kW (32A) will add about 30 miles per hour. Charge times various depending on the vehicle, how flat the battery is and temperature.

Which charger do you get?

When chargers were 'dumb' they all did the same job - they were basically just 32A AC wall sockets. But now that many chargers are "smart", their functionality does vary and choosing which charger to buy can be a bewildering. For some, it might be whatever charger their local electrician or OLEV installer recommends or is solely fitting. For others, it might be a case of choosing the brand and model of charger they want, then find an installer who can supply and fit it, which is often provided by the charger manufacturer.

The design, colour or look of the charger might be important for some, as you'll be putting on the front of your house. For example, Rolec chargers are available in a host of different colour combinations, EO make the smallest unit and Andersen offer a stylish designer look to theirs. However, do remember you could simply hide the charger behind a shrub or plants instead.

For most, it will come down to price and Rolec have always been the cheapest and most popular in the UK. But as always in life, you generally get what you pay for, so the more money you spend, the quality will generally improve. Smart chargers come with an app or web interface to control the charging. You may want to also look at the functionality of this too.

A good source of information is the Rightcharge comparison website for electric chargers.

Some of the common home charger brands are:

There's plenty of information on the internet. This video here might help as as start.

This video explains how the Ohme wall charger or plug in cable charger works and how you can take advantage of cheap rate electricity tarrifs.

Tethered or untethered?

Many charge units come with a choice of either a tethered cable or a just a socket. This is down to personal preference. One has built-in cable ready to plug into your car. The other has no cable and just a socket, so you use the charge cable that comes with your vehicle.

The socket version has no cable, so you use the type 2 charge cable that comes with your car. The advantage is that it's future proof and can charge any type of EV regardless of it's charging port type.

The tethered cable version has the charging cable built-in. This is quicker and more convenient to use, but looks a little ungainly if its on the front of the house. You are also limited to the type of vehicles you can charge, due to fixed cable and plug at the end - either a type 1 or type 2.

Socket charger (untethered)

  • Can charge any car with any connector, as you use the cable from the car

  • Looks neater, less cluttered on the outside of your house

  • Slightly less convenient as you have to get the cable from your car and plug in at both both ends & return cable to car when you leave

  • Can use different length cables

  • Future proof - change your car in the future with a different socket - just use a different cable

  • Cheaper

  • Can make into a tethered by buying a second cable and leaving it plugged in

Tethered cable charger

  • More convenient- just plug one end into the car

  • Cable is fixed to the charger and looks untidy when not in use

  • Cable needs to be wound up around charger unit

  • Type of socket is fixed - no good if you want to charge cars with different charge ports

  • Not future proof - while it is possible to change the tethered cable on the charger in the future, the cost is around £120 for a new cable, plus fitting

  • Typically £100 more expensive

My own preference has always been for a untethered charger. It is then future proof and if you change your vehicle or have family and friends visiting who may need to use your charger, a socket will work with all vehicles. Using a tethered cable charger, you are limited to either a type 1 or type 2 connector on the end of the cable and therefore limited to only charging those EVs with that type of socket. With an untethered charger, you also have the option of buying a second charge cable and leaving it in the charger, so you don't need to remove the cable from the car each time you need to charge.

Charging from solar panels

If you have solar PV installed at your premises, then you should look at a charger that has solar diversion functionality. This means that you can charge your car using excess solar power, rather than exporting it to the grid. This is particular beneficial if your car is often parked at home during the day, when the solar panels are producing the most and the house is using the least. You then get free fuel in the car and also still get paid the feed-in tariff!

The most popular and high recommended charger is the Zappi from MyEnergi. See this blog page for a comparison.

Zappi charger available as tethered and socket units

Watch these videos to learn more about how the Zappi works

Charger installers

The full UK wide list of OLEV approved installers is here.

If you're local in the Oxfordshire area and surrounding counties, then I recommend LKT Electrical in Bicester. Say Matt at Go Green Autos sent you!

Charger installations without the OLEV grant

There are circumstances where you may want a charger installed and not use the OLEV grant. This could be because:

  • A wall charging unit doesn't qualify for the grant, typically because it isn't the new 'smart' type.

  • Your parking spot at home may not be technically "off-road", even if the cable doesn't trail across a pavement and therefore can't qualify for the OLEV grant.

  • You have sourced a second hand wall charger.

  • You have sourced a cheaper unit yourself online or from an electrical wholesaler.

  • Your installer isn't OLEV approved or has stopped doing grant funded installations (getting more common now due to delays in payments from OLEV).

  • You may want to install a charger at other locations, like a second home.

In these circumstances, you just pay the full installation costs. You may know an electrician who can do the installation and sometimes you get a charger installed almost as cheap as a grant funded one anyway.

One cheap option could be to simply get an electrician to install a 32A commando socket. This will still involve running a new feed cable from the distribution board.

Then use an Ohme smart cable with a commando plug on the end. You then have a tethered smart home charger with all the functionality of other smart chargers.
Octopus Energy have partnered with Ohme and you can get a discount on an Ohme smart cable via Octopus.

32A commando socket

Electricity tariffs

Due to the increased use of electricity when you get an EV, you'll want to make sure you're on the best electricity tariff. You may want a 'green' tariff so you charge your car with renewable energy. However, the UK grid generation now has a high proportion from renewables (solar, wind turbines, tidal etc) and more is being added all the time. When charging your EV over night, its likely that most of the energy is from wind turbines out at sea anyway.

Many energy companies offer a EV tariff where you get cheaper electricity at off-peaks times. This is similar to the old Economy-7 system, where you had cheaper electricity during the early hours to heat up your electric storage heaters.

Octopus Energy have two tariffs worth considering for EV drivers. The 'Go' tariff gives you cheaper electricity between 12.30-4.30am, which is long enough to charge most EVs. Electricity during this period is a 5p per kWh, which is typically a third of the daytime rate. You then use your smart charger or in car scheduler to delay all your charging to 12,30am. Your motoring costs will reduce from around 3p per mile to 1p per mile. Use my referral link for a £50 credit if you switch to Octopus Energy.

The 'Agile' tariff is more interesting as this tracks the national grid demands and pricing in half-hour bands. At peak rate you pay more, but at during off-peak periods or at times where demand is low or the amount of renewable energy generation is higher than the current demand, you pay significantly less. At sometimes the price goes negative, which means you actually get paid to use electricity. So sometimes during a very windy night when the demand on the grid is low, yet the wind turbines are spinning furiously, you end up getting paid to charge your EV or put on the washing machine! During the covid pandemic, when many businesses were shut, prices also went negative during the day too. Use my referral link for a £50 credit if you switch to Octopus Energy.

Charging at work

Businesses can install chargers for their own fleet, staff and visitors. OLEV grants are also available most home installers will also quote for workplace installations, or you can just get your local electrician to install the charge points.

If you're looking to make your chargers available to the general public, then you'll probably want to also talk to the national charger networks, such as PodPoint, and consider a managed solution.

Public charging

The public network is made up off charging stations from a number of different providers. While chargers in retail parks, supermarkets and hotels are often free to use, most require payment. This is where it gets complicated for new users as most chargers need an app on your smartphone to handle the payment and to activate the charge. Things are changing though and chargers are now appearing where you simply just tap your contactless credit or debit card to start the charge. These are often in petrol stations.

For more information about charging in public, see Public Charging and Zap Map Guide to Public Charging Networks.

This page was last updated 05/07/2020