This is how many solar panels are needed to charge your electric car

The fact that some Dutch people can charge their electric cars for free is thanks to solar panels. But how many panels do you need to charge an electric car?

The panels allow electric vehicle owners to charge their cars for free. At least if you don’t generate too much electricity. Energy suppliers have recently started charging feed-in costs for excess electricity, making solar panels less popular. So we don’t want too many panels on our roof.

How much electricity does a solar panel produce?

The output of solar panels is expressed in Wp, an abbreviation for Watt Peak. This is how many watts a solar panel can generate under optimal conditions.

In general, a solar panel produces around 350 Wp. In practice, however, you have to multiply this number by 0.88 to get a realistic annual electricity yield.

A 350 Wp solar panel produces approximately 308 kWh of electricity per year. Although solar modules produce more output on sunny days, for simplicity we divide the 308 kWh by 365. This corresponds to approximately 844 Wh per day per module.

Amount required to charge an electric car

Let’s say you (soon) own a Volvo EX30. This electric car has a standard battery capacity of 49 kWh. In practice, it will rarely or never happen that you park it in the driveway with 0 percent charge, but in this example we are counting on the full 49 kWh. Theoretically, it takes no less than 58 solar panels to generate that much electricity on a sunny day. The charging losses are not even taken into account.

Do you actually want to use the electricity you generate to charge your car, especially with a view to phasing out the billing regulation? Then you also have to charge your electric vehicle during the day, when the solar panels make optimal use of the light. In practice, night is the time when electric cars are charged at home. Installing a home battery could be a solution in this case.