How Long it Would Take to Use Solar Panels to Charge an Electric Car (EV)

How long would it take to charge an electric car (EV) with solar panels? This is a common question we see. The truth is, the answer depends on various factors including the size of both the solar system and the EV charger, also don’t forget about, the specific car battery in question. There are so many factors to consider that there is not on answer that fits all scenarios. Therefore, this article will break down the factors that influence how long it takes to charge an electric vehicle with solar panels.

How many kWh does it take to charge an electric car?

The amount of energy needed to charge an electric car typically ranges from about 30 kWh to 100 kWh, depending on the size of the car’s battery. For example, a standard electric vehicle with a 60 kWh battery would require approximately that much energy to fully charge from empty. However, actual consumption can vary based on factors like driving habits, battery efficiency, and environmental conditions. So to answer your question as to how long it would take to charge electric vehicles with solar panels, we need to also take into consideration the following factors.

The electric vehicle’s battery size

Let’s start with the electric vehicle’s battery size. A small electric car would have a smaller battery than a larger electric SUV and therefore a standard solar system with a 5 kW inverter and about 10 kW batteries is likely sufficient enough to charge it overnight. However, another consideration, is the percentage charge that is still in the battery or how empty the car battery is. Charging a fully discharged battery would take twice as long than a battery that’s been 50% discharged.

The size of your solar panel system

The size of your solar panel system, or how many solar panels you have, also significantly impacts the time it takes to charge your electric vehicle. A larger solar array generates more electricity, allowing you to harness greater amounts of energy to charge your electric car more quickly. For example, if your system produces ample power during peak sunlight hours, you can fully charge your vehicle in a fraction of the time compared to a smaller system. Conversely, a smaller solar system setup may not generate enough energy to meet your charging needs efficiently, potentially extending the charging duration.

The type of electric vehicle and individual driving patterns

If you do a bit of mileage with your electric vehicle and need to fully charge the battery every day, your ideal scenario may be installing a larger solar panel system that comprises would of 10-13 kW solar panels, 10 kW inverter and 10-15 kW batteries. This is for people who churn 100-200 km a day and need the battery recharged to a safe point and void range anxiety. Most people will easily manage with 6- 10 kW solar panels, 5 kW inverter, 10-15 kW batteries and would have to recharge their car batteries every few days as needed.

The type of EV charger and specifications

The ideal situation would be commute to work, leave the car on a slow to medium charge to ensure the car is charged enough and ready to go back home from work. Again, this depends on the charger size available. EV chargers also come in different sizes and specifications, which also affects charging speed. You may have a large enough solar power system but if your EV charger size is too small, you won’t be able to maximise it.

Most electric cars come with a 1.5kW portable charging cable which chargers at a rate of approximately 1.5kW per hour. However, this may not be enough for those wanting to utilise solar power to charge. For this reason, dedicated EV chargers are a popular choice. The most popular sizes for EV chargers are 7 kW for single-phase systems and 22 kW for three-phase systems. These higher kW charging stations can make charging your EV battery with solar much faster.

Whether you have three phase vs single phase power

The choice of one or another would be determined by the battery size of your electric vehicle and how often you need to charge it and who quickly, but also whether you have a single or three phase meter at the charging location you intend to install it. Homes with single-phase power use one live and one neutral wire for residential applications, while three-phase power homes employ three live wires for efficient distribution in industrial settings.

If you have a single-phase meter the maximum you can charge at any time would be 5 kW since that is the size of your inverter. Alternatively with a three phase meter you can charge up to the size of the inverters total capacity that can be from 5 to 20 kW or more depending on the approved size from the utility company. This unfortunately depends entirely on the location, the policy and infrastructure available in your suburb. Some suburbs have inverter sizes limited to 5 kW single phase, others have three phase and plenty of available capacity from the local transformers previously installed.

Want to start using solar power to charge your electric car? Contact e-Solar today!

The interesting thing about the latest EV chargers is that they can charge your vehicle exclusively with surplus power generated by your solar system, ensuring that excess energy isn’t exported or used to charge your solar batteries when they’re already full. Depending on your needs and situation this feature can be over-ridden, but it’s very handy as you don’t have to worry about when your charger is on or off depending on the weather or your home load consumption at night.

It goes without saying that if you can charge your electric vehicle every weekend with solar power, you’re not only saving money but essentially charging your car for free. Want to start charging your electric vehicle for free with rooftop solar panels? We’re here to help! e-Solar is one of Perth’s longest-running solar companies. Contact the friendly team at e-Solar for a tailored home solar system with EV charging station.