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There may be no stopping the electric vehicle (EV) revolution. In March 2023, half of all new retail vehicle registrations in the San Francisco market area were electrified  — hybrid, plug-in hybrid or full EV. Harnessing the free and renewable power of the sun by integrating solar panels onto an EV’s surface offers the promise of self-charging vehicles.

If EVs can generate enough energy to charge their high-voltage batteries, it will decrease “range anxiety,” overall operating costs, smog and the strain on the power grid. Currently, EVs charge their batteries in part through regenerative braking systems. Depending on driving habits and the weather, solar panels in conjunction with regenerative braking have the potential to add thousands of “free” miles per year.

So why aren’t all EVs already covered with efficient solar panels? Because EVs lack the surface area to generate enough solar power to recharge their batteries.

Who Is Making Electric Cars With Solar Panels?

Many car manufacturing startups are promising solar electric vehicles (sEV). Manufacturers offering vehicles with, or planning to offer sEVs, include:

• Hyundai: Its Ioniq 5 offers a solar panel roof option which, according to Hyundai, can add up to 1,200 miles a year of additional range.
• Mercedes-Benz: Plans to bring its solar panel roof Vision EQX concept to market by the end of 2023. Mercedes-Benz says the EQXXprototype adds up to 15 miles of range a day, or 3,750 miles a year.
• Fisker, Inc.: The Fisker Ocean, slated for delivery in fall 2023, offers an optional full-length solar panel roof projected to add 1,500 miles per year.
• Lightyear: It designed its EVs for solar-powered driving, claiming up to 43 additional miles per day from 54 sq. ft. of solar panels.
• Sono Motors: The Sion was said to be completely covered with solar panels and promised 3,500 miles a year from solar power. But Sono ended its car program before bringing a model to market.

What percent of the EVS currently manufactured have solar panels?

Probably less than 1%.

Data on the percentage of sEVs manufactured is scarce. With record-breaking sales of EVs in the U.S. in 2022 estimated at just under 1,000,000, sEVs are barely a blip on the radar. It’s comparable to EVs 10 years ago, with 90,000 EV vehicles versus 15,000,000 with internal combustion engines (ICE) — about half of one percent of all U.S. car sales.

How Do Electric Cars With Solar Panels Work?

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Solar panels convert the sun’s light particles (photons) into usable direct current (DC).

Solar panels feature individual photovoltaic cells made from silicone and other semiconductor materials. When sunlight strikes a cell, these materials create electricity. Direct current generated is easily stored in an sEV’s low- or high-voltage battery.

EVs with small solar panels produce enough power to operate low-voltage systems like headlamps, the A/C cooling fan, windshield wipers and infotainment systems.

Benefits of Solar Panels on EVs

Saving money is the main benefit of charging EV batteries with sunlight. Other advantages include:

• Increased driving range;
• Reduced carbon footprint;
• Lighter and smaller energy-dense batteries;
• Aerodynamic styling lowers wind resistance.

Are there any drawbacks?

Yes. Most importantly, batteries can’t be charged at night or when it’s raining.

Other hindrances include:

• The expense of adding solar panels to EVs;
• Areas of the country may lack the “ideal conditions” for charging EVs;
• Panels must be kept clean and maintained for maximum efficiency.

What Do Solar Panels on EVs Mean for the Future of Driving?

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For the near future, manufacturers will remain cautious before pushing forward with integrating solar panels in EVs. However, as solar panel technology improves, it may potentially play a significant role in powering the transportation sector as it transitions from internal combustion engines (ICE) to EVs.

EV add-on solar panel kits can produce about 50 watts of electricity to charge the low-voltage battery. But beware: DIYers should not be working on an EV’s sophisticated electronic systems — especially the high-voltage system.

Will Charging Stations Become Unnecessary?

No. EV charging stations will be around for years.

If you’re looking to buy a new EV to lower your energy costs and carbon footprint (and qualify for a $7,500 tax credit), adding a solar array to your home to charge your EV makes the most sense.

Based on U.S. averages, six to 10 solar panels should charge your EV battery from 20 to 80 percent capacity in four to eight hours. This is true if you:

These factors and others affect charging rates and times.

Final Thoughts

The notion of using solar panels to self-charge an EV is intriguing. It’s like asking an ICE vehicle to produce its own gasoline — a novel thought, but not feasible. Current solar EV technology doesn’t offer a cost-to-efficiency ratio to justify the added expense.

However, according to an MIT Technical Review, batteries constructed from carbon fiber solid-state cells and other emerging new battery technologies will dramatically increase performance. And that’s key because solar panels are becoming super efficient as battery performance improves.

Couple that with progressive body shapes made from lighter materials (like titanium), and it helps make sEVs a reality. That cannot come a moment too soon.

Research by author Robert N. Charette shows meeting infrastructure demands to support EV growth, along with the goal of 100% clean power by 2035, are logical but not realistic. Several states plan to ban ICE sales in 2035. However, he says the power grid uses “inadequately sized transformers.” Plus, he says, “the failure to issue permits for new electricity transmission lines” are roadblocks to these lofty objectives.

Generating their own power from body skins fabricated from solar panels and storing that energy in their own batteries will make sEVs an attractive option. Solar-powered EVs are the future. We’re just not sure when that future will arrive.