How big does a photovoltaic system need to be to effectively charge an electric car?
More and more households are opting for electric cars and want to rely on solar energy at the same time. A frequently asked question is: How many solar modules are needed to cover the electricity requirements of an average family household including an electric car?
In this article, we explain how you can calculate your requirements and what is important.
What is the electricity consumption of an average single-family home?
A typical 3 to 4-person household in Germany consumes between 3,000 and 4,500 kWh of electricity per year. This figure varies depending on the size of the household, habits and the household appliances used, such as the fridge, washing machine or dishwasher.
How much electricity does charging an electric car consume?
An electric car is an additional electricity consumer. On average, an electric vehicle requires around 15 to 20 kWh of electricity per 100 kilometres. With a mileage of around 12,000 kilometres per year, the annual electricity consumption of an electric car is around 2,000 to 2,500 kWh. The total electricity requirement of a household with an electric car therefore increases to around 5,500 to 7,000 kWh per year if the vehicle is only charged at home.
How effective is the power generation of solar modules?
The electricity production of solar modules depends on various factors, such as the size of the system, the location and the orientation of the modules. In Germany, a solar system with an output of 1 kWp (kilowatt peak) generates an average of 850 to 1,200 kWh per year. A system with 1 kWp usually consists of around 2 to 3 modules.
How many solar modules are needed to charge an electric car?
To cover a household's electricity requirements of around 6,000 kWh per year (including an electric car), a solar installation with an output of around 6 to 7 kWp would be required. This means
A 6 kWp system generates around 5,100 kWh per year.
A 7 kWp system produces around 5,950 kWh per year.
A 7 kWp system usually consists of 16 to 18 solar modules, depending on their output.
Is my PV system sufficient to charge the electric car?
A 7 kWp solar system can cover the majority of a household's electricity needs, including charging an electric car. However, it depends on the time of year and the amount of sunlight whether the entire demand can be covered by solar power. Especially in winter or for longer journeys, additional electricity from the grid may be required.
Conclusion: This is what the photovoltaic system must be able to do to charge an electric car!
For a 3- to 4-person household with an electric car, a solar system with an output of around 6 to 7 kWp is usually sufficient, which corresponds to around 14 to 18 solar modules. However, the exact number of modules required depends on individual factors such as roof orientation, angle of inclination of the roof, shading of the modules, driving habits and general electricity consumption.
With a solar system, you can cover a large part of your electricity needs sustainably and save costs in the long term - even if you still use it to charge your electric car.