Can You Charge Electric Cars with Solar Panels?

solar panel charging a car

Even though it costs 70% less to "fill" an electric car compared to a gas-powered car, many EV owners are still looking for ways to bypass oil & gas-generated electricity.

One such way is to use solar panels to charge your electric car. 

This, of course, benefits the environment but, in turn, has the ability to completely reduce the amount you spend on charging your EV nonetheless. 

The question is, is it even possible to charge your electric car with solar panels, and if it is, how many would it take to do so?

In order for you to figure out how many panels you'll need to charge an EV, you need to begin by calculating the following:

 In this article, we aim to cover each of the above points. Let's get started. 

Can you charge electric cars with solar panels?

charge electric cars with solar panels

So, is it possible can you charge an electric car with solar panels? The short answer is, yes, you absolutely can. And in our opinion, it may be the best way to charge your EV, especially if you are looking to save on costs.  

The question you rather want to be asking yourself is, how many solar panels will it take to charge my EV. 

If some of you have already purchased a solar generator from us, you know that charging with solar input can take some time (weather dependent), and that's when the battery being charged has a capacity of 2000Wh. 

The Nissan Leaf, for example, has a battery capacity of 40,000Wh. 

This means you are going to need some serious solar power to get this thing charged in a reasonable time frame.  

Let's find out how much.

How many solar panels do I need to charge my EV?

To calculate just how many solar panels you will need, we need to use the following below formulas.

The first formula calculates the daily energy (kWh) required to charge your EV. It also considers its power consumption and the miles you drive.

The second formula looks at the power required by calculating the DC size of your PV system, it does this by factoring in peak hours of sunlight and a derating factor attached to PV losses.

 

Then lastly we need to figure out how many solar panels you'll need to get the charging done. This is pretty simple and involves dividing the total DC size of your system by the generation capacity of your panels.

 

By using the above formulas, it is pretty easy to determine how many solar panels you will need to charge your EV.
Let's create an example:


(Please note for this example, we will consider the following: You live in California and receive an average of between 5 – 7.5 kWh/m2/day.)


Lets's get started. You own a Tesla Model 3. This EV has 353 miles of autonomy and consumes 14.9kWh every 62.13 miles.

That brings us to the second calculation required, that is the DC size of your PV system.

Now that you know the DC Power required to charge this specific EV model, you need to calculate the total number of panels you will need.

Based on the calculations above we can see that you will require six 400 watt solar panels to charge your Model 3. 

How long does it take to charge an electric car with solar panels? 

charge an electric car with solar panels

This really all depends on where you live, that is how much Global Horizontal Irradiation (GHI) you receive, how many miles you need to drive each day, and what size solar system you have installed. 

But once again we can assume the below. 

You own a Tesla Model 3, which has 353 miles of autonomy, and consumes around 14.9kWh every 62.13 miles.  

Assuming you lived in California, and drove 62 miles each day, you would require a 2400W solar system to recoup your lost capacity within 6.25 hours. 

Now bear in mind if you drove half that distance you would require half the amount of time to recoup your last capacity. This is of course assuming you want to completely recoup your lost capacity at all. 

Remember the Model 3 has 353 miles of autonomy, meaning you could go a few days without charging and still be fine.

Is it worth charging your electric car with solar panels? 

In our opinion, absolutely. 

A solar system could essentially keep your electric car charged 365 days a year. This could potentially provide you with enough solar savings for a payback period of roughly 8 years.

Considering solar systems last up to 25 - 30 years, once you have paid off your PV system, you could charge your EV for $0 for up to 17 years or more.

Not only will you be saving money when it comes to charging your electric car, but a solar system will also allow you to generate free electricity effectively doubling your ROI. 

Final Thoughts

Ideally, to charge an EV with solar, you would need a large PV system, ideally something over 3000 watts (location dependent). Additionally, if you were also wanting to power your household appliances alongside your EV, you are going to need an even bigger PV system, likely something over 15,000 watts. 

However, you may also be able to use your Bluetti solar generator to charge your EV.

Do not expect to get much range by doing this, but if you are out in the middle of no where stuck high and dry, a few extra miles could make all the difference. 

When doing this though, it is very important that you reduce the charge current to below the amp rating of the power station you are using. If you fail to do this your generator will be unable to charge your EV. 

But this is topic we aim to cover in a future article. Until then, stay tuned.