Can I use Solar Panels to Charge my Electric Car?

Electric cars, commonly referred to as EVs, are gaining popularity in the UK due to the push for a more environmentally friendly nation. More than 265,000 electric cars were registered in 2022, which is a growth of 40% on 2021. Whilst being a green solution for drivers, 40-50% of the total electricity production in the UK is still generated by fossil fuels, so electric vehicle owners are turning to household solar power solutions in an attempt to go completely green.

But is it possible? This blog post will explain if it is possible to charge your EV, and any alternatives to help decrease your energy bills.

How much electricity does my EV use to charge?

Most, if not all, electric cars will have a Type 2 connector which can charge through an EV charger up to 22kW AC. However the most popular EV charger in the UK is a 7kW AC fast charger which you can have installed as a home charge point. This means you can charge your vehicles battery at 7kW every hour. A three-pin plug inside your home charges at 3kW AC.

The amount of electricity your electric vehicle will use to charge depends on the battery size of your vehicle which averages around 40kWh.

Can I use solar panels to charge an electric car?

Yes, installing solar panels to your house can generate enough electricity to charge an electric car but not all-year-round and not to 100% capacity.

As mentioned, the average battery capacity for an EV is 40kWh and if we based the average mileage a day at around 40miles this would use around 25% of the vehicles battery. The average house has enough roof space for between eight to ten solar panels which would generate around 4000 watts of solar power.

Based on these figures, we have attached a graph below which shows the average daily per figures month of:

• how much power is required to charge your electric car by 25% (blue),
• the amount solar energy based on eight to ten solar panels would generate on average* (yellow)
• and how much shortfall in power you would have between the two (red).

*Based on London solar irradiance figures

As you can see having eight to ten solar panels installed to your roof would generate enough electricity to charge an EV by 25% everyday April through to September. However, whilst you could save money in the winter months, you would still need to rely on a second source of power to generate the electricity to cover the shortfall.

In conclusion, whilst charging your electric vehicle off-grid is possible in the summer, it’s an expensive option and there are alternatives which are beneficial in reducing the overall household electricity bills.

What are the alternatives?

On-Grid System

An On-Grid System would allow you to save money by using solar energy where available to charge your car, and then topping up the system through the grid when no solar energy is available. The average on-grid system could save you on average £1,400 a year, based on our figures, and as the system is installed to your house any electricity generated by solar could be used within your house too.

You could also look at adding a Battery Storage System in conjunction with an On-Grid system to store the energy generated by the solar panels that you don’t use during the day and then use this when solar isn’t available in the dark evenings and overnight. 

Read more about our On-Grid Systems below:

https://www.sunstore.co.uk/solar-power/on-grid-solar-systems/

Home Battery Storage System

A home battery storage system acts like a large power bank for your house. It stores electricity from the grid and then you can use this electricity at a different time. The best way to take advantage of this type of system would be to register for a flexible tariff (sometimes called Economy 7) which measures your electricity usage based on different prices per kilowatt: an on-peak rate and a much cheaper off-peak one. You then store the electricity during these off-peak hours whilst the cost is lower and then use the stored electricity during on-peak hours where the cost is much higher.

This means you could store electricity overnight from the cheaper off-peak rates and then use this electricity for charging your electric car during the on-peak times.

To understand more about Home Battery Storage Systems, take a read of our previous blog post below or view our Lithium Battery Storage System:

https://www.sunstore.co.uk/2023/02/08/saving-money-with-home-battery-storage/

On-Grid Lithium Battery Storage System