Charging your EV at home : what do you need to know ?

Home charging solutions for your electric vehicle 

First and foremost, in this article, we are only looking at charging solutions for individual housing. For example, homes with a garage or a private, enclosed parking space. 

To find the ideal charging solution for your particular case, you must take several factors into account. Your travel needs, your vehicle’s charging capacity, your electrical installation and your budget must all be factored in to find the best solution(s) for you. 

Disclaimer: Prices and costs mentioned in this article are relevant for France but might be inaccurate depending on where you live.

1. Ordinary household outlet 

Let us start with the most accessible means of charging. All electric cars can be plugged into an ordinary electrical socket at home using the connecting cable supplied with the vehicle.
 

Caution

However, while this solution is okay for emergencies, it can pose some serious safety problems. Household sockets are not designed to charge an electric vehicle. The risks of overheating are high, especially if you plug your vehicle in for a long time. 

For safe use, you need to have a separate socket connected up to the fuse board individually and protected by a 16-amp fuse. This means you will avoid tripping the main circuit breaker when another appliance is connected up to the same circuit or in the event of overheating. 

Red flag: if you do not have an electrical socket in the garage, you might be tempted to use an extension lead to reach your vehicle. For obvious safety reasons, this is highly inadvisable.

Power rating and charging time 

On a household outlet, the maximum power rating delivered is 2.3 kW (10A), which means you need at least 10 hours to charge your vehicle. 

Plugging a vehicle into an ordinary socket for so long is a highly risky business. It is even more hazardous if you leave your vehicle plugged in overnight.  

We therefore recommend that you should only use this method of charging as a last resort and under close surveillance.

2. Heavy-duty socket 

Description and price 

To benefit from a charging solution that is not only safe but affordable, a heavy-duty socket like Green’up is the minimum requirement. 

In contrast to a standard socket, the heavy-duty version is a more robust, reliable means of charging safely. One of the biggest differences is that a residual circuit breaker is delivered with the socket. Its purpose is to protect against electric shocks and cut off electric circuits in the home in the event of overloading. 

It costs around 150 to 200 euros (£130 to £175) to buy the complete kit (socket + residual circuit breaker). Although it is not compulsory for this type of installation, you can call on an electrician to install the socket. He can also check that your electrical installation meets the current standards.

Power rating and charging time 

This solution offers a maximum power rating of 3.2 kW (14A). 

The charging time mainly depends on your vehicle’s battery capacity, given in kWh. To top up from 20 to 80%, you will need about 10½ hours to charge a Renault Zoé (50 kWh), 7½ hours for a Fiat 500e (42 kWh) and 6½ hours for a Volkswagen e-Golf (32 kWh).

It should however be noted that the heavy-duty sockets marketed under the Legrand brand only deliver 3.2 kW (14A) if you are equipped with the right cable (not all cables supplied with electric vehicles are). If not, the charging power might be limited for your vehicle.

3. Charging station or charger 

Finally we come to the most advanced solution – the charging station. For a higher price, you can have a charging station installed and benefit from significantly faster and safer charging. 

To install a charging station at your own home, here are 2 AC charger solutions that are suitable for everyday use:

Installing a single phase charger 3 to 7 kW

This first type of charging station offers slow charging and is appropriate for most usages. If you use your electric vehicle for everyday travelling and occasionally go off for a weekend or on holiday, this type of charger is perfectly sufficient. 

Depending on the charging capacity of your vehicle and how often you drive it, you can opt for a charging station with a maximum power rating of 3.7 kW or 7 kW.

In terms of budget, we are talking of a minimum of 1200 euros (£1,000), including installation.

Installing a three-phase charging station 11 to 22 kW

This option offers fast charging. It is designed more for drivers who go on long electric journeys on a regular basis and who need a rapid charging solution so they can set off the following day with a fully topped-up battery. 

Of course, this type of charger is only suitable for vehicles with a charging capacity that corresponds to these power ratings. If this is the case, you can opt for a charging station with a power rating of 11 kW or 22 kW.

In terms of price, we start at around 2000 euros (£1700), including installation. Unlike a heavy-duty socket, you need to call on a qualified electrician to install a charging station. 

The final price obviously varies from one service provider to another and depends on where you live and the type of charging station you go for. There are also a number of optional extras such as remote charging control and power rating adjusters to name but a few. 

Also, remember to check if home charger grants (e.g.: OZEV grant in the UK) are available in your country. You might qualify and get a good discount.

Power rating and charging time 

The major advantage of a charging station is that it saves time. For a Renault Zoé 50 kWh, you need between 8½ hours on a 3.7 kW charger and roughly 1½ on a 22 kW charger for a top-up of 20 to 80%.

How much does it cost to charge my electric vehicle at home?

Electricity tariffs 

Charging at home is undeniably economical. The tariffs applied are the same as for the electricity supply to the rest of your home. 

If you charge your electric vehicle at home, it might be interesting to look into off-peak tariffs which could mean you can charge your vehicle overnight at a better rate.

You need to look into the various offers made by your electricity supplier and maybe consider switching to green energy, which may be a little bit more costly but is still less expensive than running a car on petrol.

Calculating the cost of home charging 

In practical terms, the cost of charging an EV at home depends on 2 factors:

1. How much energy your EV consumes: this usually varies between 12 and 20 kWh/100km
2. The rate per kWh invoiced by your electricity supplier: for the sake of the following example we’re going to take a tariff of €0.1593/kWh at the full rate and €0.1244/kWh during off-peak hours. 

If your vehicle consumes 15 kWh/100 km on average, the cost of charging will be €2.39/100km at the full rate (15 x 0.1593) and €1.87/100 km during off-peak hours (15 x 0.1244). 

Once again, the cost varies between countries. In the UK, the average cost is estimated at around 4p per mile (£4/100 miles).

Example: Let us take a Peugeot e-208 in France (50 kWh battery)
→ Recharging from 20 to 80% will cost €4.75 at the full rate and €3.71 during off-peak hours.

If you want a quick estimate of the home charging cost for your EV model, there are several charging cost simulators online.

It goes without saying that the amount of energy an EV consumes varies from one driver to the next. If you want to optimise your electric vehicle’s range and therefore save money on charging, consult our article on the principles of eco-driving.

In short 

To charge your electric vehicle at home, this is what you need to remember from the 3 options:

1. Charging from a standard household outlet is highly inadvisable for safety reasons. It should only be used as an “emergency” solution under the driver’s strict surveillance. Using an extension lead is prohibited.
2. Charging using a heavy-duty socket like Green’up is an interesting, low-cost alternative and is much safer than a standard household outlet.
3. Charging using a dedicated charging station is the most costly solution, but also the most reliable, safe and flexible answer depending on your particular usage.

Finally, to estimate the cost of charging at home, use the following formula:

Your car’s energy consumption in kWh/100km x rate per kWh charged by your electricity supplier. 

💡 We hope you have found this article on charging your electric vehicle at home helpful. As we stated at the beginning of the article, the solutions we have given are meant for individual homes. We will be looking into the issue of charging when you live in collective housing in a future article. Until then – stay connected 😉

And what about you, do you charge at home? What solution have you opted for? Share your experience with us and add your tips in the comments 👇



Photo credit: Ed Harvey on Unsplash