Electric Car Charging Guide

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Electric Car Charging Guide

What happens when you run out of fuel in your car? You stop at the nearest filling station, get it refuelled, pay the charges, and go along your way.

How about when your car doesn’t run on fuel and uses electricity instead?

Electric cars (EVs) are relatively new in the market but have surely taken it by storm. The UK has seen exponential growth in the use of electric cars with more people willing to make the switch from fuel-powered vehicles.

This change is partly due to the Government’s plan to ban the manufacturing and sale of petrol and diesel cars by 2030.

The biggest advantage of electric cars and the key reason why so many people are attracted to them, and why the government is encouraging their adoption, is that they are better for the environment and produce no harmful emissions.

Other than that, they offer high-quality performance, require less maintenance, are quieter than fuel-powered vehicles, and are generally better for you and the environment in the long run.

However, since they are still fairly new, there is a shroud of mystery, uncertainty, and unfamiliarity regarding electric cars, particularly electric car charging, which is an important part of owning an electric vehicle.

We have created this detailed electric car charging guide to cover all the key areas related to EV charging, the different types of chargers to choose from, how much it would cost, how long it would take, and much more:


You can charge your electric car in any of these 3 places: at home, at work, or a public charging station. Let’s look at each one in detail:


Having the option to charge your electric car at home according to your convenience is surely a lucrative thought and a big reason why many EV owners opt to install a home charging station.

While it is possible to use a standard 3-pin socket to recharge your EVs, it is not the recommended way since it carries serious fire risk.

It is best to opt for a wall-mounted charging point, which is also the most common type of EV home charger and can be installed inside your garage or outdoors on an external wall near the driveway depending on your requirements.

Since most cars are usually parked at home at night, it makes it easy to charge them using home EV chargers overnight and always have the electric cars ready to be used in the morning.

The cost of charging is also cheaper when done at home since you can make use of night-time charging which, in most cases, is the cheapest time to recharge your EVs.

This not only makes home charging stations a convenient option for EV owners but also a pocket-friendly one in the long run.

When it comes to the cost of installing an EV charge point in your home, it depends on the charging units and the speed of the system.

You can expect to pay anywhere between £250 and £500 for a 3kW unit and between £450 and £800 for a 7kW unit. Please take note that these prices are merely guidelines and subject to change.

The good news is that the UK government provides financial support for EV owners looking to install a home charging station through their Electric Vehicle Homecharge Scheme (EVHS) that helps offset the installation charges.

According to the EVHS grant, also called the Office for Zero-Emission Vehicles (OZEV) grant, you are eligible for up to 75% cost coverage of a new wallbox charger with a maximum contribution of £350 per charge point.

To qualify for the grant, you must:

  • Own an eligible EV or PHEV, or leased one for at least 6 months,
  • Have off-street parking at your home,
  • Install an OZEV-approved charge point,
  • Use an OZEV-approved charge point installer, like Calder Electrical.


Charging points at work offer another convenient way to recharge your vehicles while they are parked during the day.

It is important for employers to offer this facility to their employees since, aside from your home, your workplace is where you spend most of your time.

People who do not have home charging facilities can rely on their workplace to fulfil their EV charging needs. It may even allow them to consider owning an electric car in the first place without having to worry about where to charge it.

People with EV home chargers can also benefit from workplace charging stations in the sense that they can easily top-up their batteries at work to increase their EVs range.

Since workplaces can expect to have different types of EVs with different charging connectivity needs, the chargers need to be compatible with the greatest number of vehicles possible.

The most common workplace EV charger installation is a wall-mounted Type 2 charger with a 7kW rate of power. This is compatible with almost all the top-rated EVs in the market and, depending on the model and battery size, can charge one fully in around 3 to 7 hours.

Some workplaces may also opt for a faster 22kW charger or a rapid charger if they have the space and budget for it. Read about the different types of EV chargers in the section below.

Similar to the EVHS grant, the Government offers financial support to businesses looking to install office EV charging stations under the Workplace Charging Scheme (WCS).

It allows businesses to claim 75% of the total cost of installation, up to a maximum of £350 per socket installed, and a maximum of 40 sockets across all sites for each workplace.

To qualify for the grant, you must:


When we say public EV charging stations, do not expect to get a full-fledged petrol station-like forecourt experience. A public charging station can simply be two or more individual charging points in the corner of a multi-storey car park.

The UK’s public EV charging infrastructure is owned and operated by several organisations including energy firms, private companies, Government departments, and charities.

In addition to these individual charging points, the local authorities are also toying with the idea of converting lamp posts into EV chargers.

There are currently thousands of public EV chargers in the UK to accommodate the mass shift to electric cars, with around 7000 new locations added in 2020 alone.

Some of these facilities require you to sign up for an account before you can use their services, while some don’t and work on a much simpler operating procedure.

You can expect to find a few public charging points that will offer the charging for free, however, more often than not, you’d be expected to pay for the facility using contactless payment options such as RFID or smartphone apps that can also track your usage.


There are three types of EV chargers – slow, fast, and rapid – and their difference is apparent by their names in terms of how quickly they are able to charge your EV.

Slow chargers

Slow chargers are mostly rated at up to 3 to 6kW, with the most common ones rated at 3.6kW. They usually take around 6 to 12 hours to fully charge an EV, though the time depends on the charging unit and the EV being charged.

Slow chargers are mostly found in homes and are used by EV owners to charge their cars overnight. It offers plenty of time to charge them with a slow charger and the night-time charging rates are much less with special off-peak rates.

These charging units are tethered or untethered, with most of them being the latter. An untethered charger has no charging lead attached to it and requires a cable to connect the EV to the charge point.

Although slow chargers are commonly used for home charging, they are not necessarily restricted to it and can also be found in the workplace and public charging stations. However, due to their long charging times, they are less common in these places and the ones that are, are usually older devices.

Although slow charging can be carried out using a standard 3-pin socket, it is not recommended to do so due to the electric cars’ high current demands and prolonged time spent charging.

It is strongly recommended to get a dedicated wallbox charger, also called an electric vehicle wall charging unit, which is installed either in your garage or outside your home – whichever is nearest to where your EV is parked.

Fast chargers

Fast chargers are at least twice as fast as slow chargers and are typically rated at either 7kW or 22kW.

Charging times vary depending on the vehicle and the charging unit, with a 7kW charger easily charging a 40kWh battery in around 4 to 6 hours. You can expect a 22kW charger to do the same in 1 to 2 hours.

Fast chargers are usually found in workplaces or public charging stations such as car parks and supermarkets where you are likely to leave your car for a couple of hours.

You can also install a fast-charge wallbox charger in your home as well, provided that your house electrics are able to support it.

Rapid chargers

Rapid chargers are the fastest way to recharge your EV, with the most common AC ones rated at 43 kW and DC ones rated at 50 kW.

They are most commonly found at motorway services and in locations close to the main route where people usually need a quick recharge to be back on their way.

Depending on the EV model, rapid chargers can charge a battery to 80% capacity in just 20 minutes. Also, all rapid charger units have tethered cables and can only be used on EVs that are capable of rapid charging.


Depending on the size of the battery and the speed of the charger, it can take anywhere around 30 minutes to more than 12 hours to charge an electric car.

As an example, a typical electric car with a 60kWh battery would take under 8 hours to fully charge using a 7kW charger.

While some EV drivers wait for their batteries to completely drain out before recharging them, others simply top up the charge instead of waiting.

Also, you might have heard that you should always charge your batteries to 80%. Why is that so? For starters, it keeps the voltage lower and prolongs battery life. Also, after 80%, the charging speed slows down significantly, causing you to wait longer for it to charge to 100%.

Some of the main factors affecting the time it takes to charge an EV include:

The size of the battery

This is kind of a no-brainer. The bigger the size of your electric car’s battery (measured in kWh), the longer it will take to charge compared to one with a smaller battery.

The state of the battery

If you are charging a completely drained out battery, it will take longer to charge it than if you are simply topping up from 40% or 50%.

Max charging rate of the electric car

Your electric car’s charging rate will determine how quickly the battery will be charged. For instance, if your EVs maximum charging rate is 7kW, it won’t charge any faster despite you using a much faster 22kW charging point.

Max charging rate of charging point

The maximum charging rate of the charge point you are using will also be directly related to how fast you are able to charge your electric car. For instance, if your electric vehicle has a maximum charging rate of 11kW, but you are using a 7kW charge point, it will charge at 7kW only.

You can reduce the time by switching to a faster charge point rated at 11kW to fully benefit from your EVs maximum charging rate.

Environmental factors

Environmental factors such as the ambient temperature play a huge role in the charging speed for EVs, particularly when it comes to rapid chargers.

Drastic temperature drops can make it slightly longer for rapid chargers to charge an electric car. Colder temperatures also make the EVs less efficient, lowering their mileage and increasing the intervals between charges.


At Calder Electrical, we can install EV chargers for domestic and commercial premises in line with the current regulations and can offer a government incentive to reduce the installation costs.

We are authorised and registered OZEV installers and our charge points come with a 3-year warranty.

If you own an EV or are planning to buy one, you will want to maximise recharge times and efficiency by installing an OZEV approved charger in your home. Our team can visit you and survey your house to help determine your needs and requirements.

There are various chargers currently in the market and it can be a little confusing to choose the best one for your home. We will take out the hassle and provide you with the most suitable and affordable option, ranging from the standard systems to the smart ones that are becoming increasingly popular.

Similarly, if you have a business that is looking to help employees or customers/clients charge their EVs at the workplace, you may contact us right away.

We offer all kinds of different options to choose from such as wall-mounted to freestanding pedestal units, and from fast charging to rapid charging units.

Depending on the size and demand of the premises, our experts will help assess the best solution for your business’s needs.

We can also offer a PAYG (Pay as you go) charging system and token fed chargers with features focused on both the user and operator. This is something a lot of businesses are looking at currently as the market for EV cars and chargers increases year on year.

Contact us here or call us on 0800 612 3001 for a quick consultation with our leading industry experts.

Photo by Michael Fousert on Unsplash