How to Charge Your Electric Car With Solar Panels: Top Considerations

Driving an electric vehicle powered by solar energy combines the climate and economic benefits of clean energy and clean transportation. “Driving on sunshine” also makes it possible for you to be self-reliant in your transportation requirements. When the power goes out in your neighborhood, you can still keep the lights on in your house and drive your car—and, as long as the sun is shining, you'll never run out of fuel.

Ways to Fuel an Electric Vehicle With Solar Energy

There are four common ways to drive on sunshine: Two involve installing solar panels on your home, and two don't. Either way, the benefits are both environmental and economical.

Solar-Powered Public Charging Stations

The simplest method: Find an electric vehicle charging station that has installed onsite solar panels with battery storage (called solar-plus-storage). They are rare, but increasingly EV charging companies are finding it cost-effective to provide electricity from solar-plus-storage, especially in times of high demand, when grid electricity is more expensive. Charging at charging stations is among the most costly ways to fuel an EV, but it's still cheaper than gasoline.

Community Solar Farm

You can also charge your EV with solar energy without installing solar panels on your home by joining a community solar farm, where electricity is generated by solar panels at a separate location from your home, then fed into the grid. With net metering programs, you get a reduced electric bill based on the amount of electricity the solar farm generated, so even though the electricity sent to your home (and EV) may not be solar, it's offset by what your solar farm produced.

Rooftop Solar

If you want to set up a solar system at home in order to charge your EV, there are also two options.

A rooftop solar system sends its electricity into the grid but also charges your vehicle when the sun is shining and the solar system is generating electricity. But most EV charging is done during the evening and nighttime hours, so, as with a community solar farm, you will in essence be charging your EV with grid electricity and offsetting it with the electricity that your rooftop solar system generates.

Solar-Plus-Storage

The second involves installing a battery storage system along with your rooftop solar panels. It's the most expensive option, but it's the best option to make sure your EV charging will be done using solar energy.

A grid-tied solar-plus-storage system can send the electricity your rooftop panels generate into the grid, into the home, into the battery, or into your electric vehicle, depending on how you program its software. The battery is your first backup energy supply, while the grid is your second. You can set your system to only charge your electric vehicle when electricity is either coming from the solar panels or from the battery itself, knowing that (if you haven't planned correctly) you can always rely on the grid.

Comparing the Costs

There are significant upfront costs to installing solar at your home, and even more with a solar-plus-storage system. But over the average lifetime of a vehicle, the savings from charging an EV with either a solar system or solar-plus-storage system can save you tens of thousands of dollars compared to fueling a comparable gasoline-powered vehicle over the same period of time. You'll also have enough electricity left over to supply all of your house's needs. Here's how it works:

EV Charging Costs

The average American travels almost 40 miles per day. To charge a 2022 Nissan Leaf, which has an efficiency rating of 30 kWh/100 miles (or 3.33 miles/kWh), would require 12 kWh per day of electricity (or 4,384 kWh/year). The average annual American household electricity consumption is roughly 11,000 kWh/year, so adding an electric vehicle means installing a 12kW solar system capable of generating 15,384 kWh/year, at an average cost of $24,509.

Add in battery storage to your solar system, and the estimated cost, based on data from the National Renewable Energy Laboratory, would be $35,991. That's not cheap, but it more than pays off in the end.

A 2022 Nissan Leaf has an MSRP of $27,400. With a federal tax credit, that cost drops to $19,900, not including any state or other incentives. Once a solar or solar-plus-storage system is installed, the cost of charging an EV is free since it costs nothing extra to generate electricity from the sun.

The average annual maintenance cost for an electric vehicle is $0.03 per mile, according to a Consumer Reports study. An average American vehicle stays on the road 11.6 years, so the lifetime cost for vehicle, maintenance, and fuel for a Nissan Leaf is $48,400 with a rooftop solar system and $59,882 for a solar-plus-storage system. (See the table below.)

Savings Compared to Gasoline

Compare that to one of the most efficient gas-powered vehicles, the 2021 Mazda MX-5 Miata (with 30 mpg), which has an MSRP of $26,830 and costs $1,900 a year to fuel. The average annual maintenance cost of a gas-powered car, again according to Consumer Reports, is $0.06 per mile, so the lifetime cost for vehicle, maintenance, and fuel for a Mazda MX-5 Miata is $56,851.

But remember that your solar system provides energy for both an EV and your house, so the savings continue. The average household uses 11,000 kWh/year and the average cost of grid electricity in the United States is $0.14 per kWh, so the average American household spends $1,540 per year on electricity, or $17,864 during the 11.6-year lifetime of a vehicle. The total lifetime cost for a Mazda MX-5 Miata plus residential electricity is $74,715, while the lifetime cost for a Nissan Leaf with rooftop solar is $48,400, and $59,882 for solar-plus-storage.

Depending on how much you drive, the vehicle you drive, where you live, the size of your solar system, how much energy your house uses, and perhaps a dozen other factors, the estimated lifetime savings of a solar system plus electric vehicle are between $14,833 and $26,315. That means that when your Nissan Leaf reaches the end of its lifetime, you've already saved enough money (or nearly enough) to pay for your next electric vehicle. Or do the math with a more expensive EV and you're likely to still come out ahead.

The Future: Solar-Powered Vehicles?

Are solar cars coming? The flat roof of an electric vehicle is the perfect place for photovoltaic cells. In theory, cover a car with PV cells and a car can fuel itself. To date, solar-powered vehicles have yet to reach more than a niche market, the product of hobbyists and college engineering challenges.

But in 2021, Aptera announced the release of a highly efficient three-wheeled, two-seater vehicle capable of charging enough solar electricity that it may never need to be plugged in. With a range of 1,000 miles, it can charge 40 miles per day, the average American commute. But until solar cells become much more efficient than they are today at converting sunlight into electricity, no passenger vehicle (let alone pickup or SUV) is capable of creating enough energy to sustain itself.