When the 2023 Fisker Ocean electric SUV begins deliveries in November 2022, the top trim will be offered with a solar panel on the glass roof.
Glass roofs are all the rage with electric vehicles, a design theme we took notice of when Tesla introduced it on the Model S in 2016 and then popularized the feature on the mass-market Tesla Model 3.
The big knock against glass roofs in EVs is the extra juice required to keep the vehicles cool in the baking sun. Solar roofs would make more energy sense: use those rays to provide range, rather than drain it.
But is it an idea that will take off? After all, a roof does not offer a large enough area to produce many watt-hours, and there is little sunlight for vehicles that frequently park indoors—hence why the new Lightyear One solar-assisted EV slathers most of its horizontal surfaces in solar panels, including the hood and rear deck.
A solar roof is a feature that is expensive and difficult to do, Fisker CEO Henrik Fisker tells MotorTrend.
"It is one thing to show a solar roof, it is another to make it work," he says in an interview. "You have to get that energy into a high voltage energy pack. It's a special converter device which we have filed a patent on. I don't know how other people do it because it is not easy to do and really get all the power in."
One thing Fisker has figured out is a way for the sun's energy to be captured by the parked car, without using energy in the car to do so. "We kind of invented something that makes that happen. We don't want to talk too much about it," the CEO says.
The Ocean has one of the larger solar roofs in the industry and will give the owner up to about 1,500 miles of additional range a year in a location like California with good weather, Fisker says.
"Under ideal conditions if you go in snail traffic on the way to work, bumper-to-bumper, you could get up to 2,000 miles a year. There comes a point where it is quite efficient, quite a lot of miles you can get free, total zero emission, so I think if you can afford it, it's a really cool feature."
"It's obviously still really expensive. We have spent a lot of time on developing it and making it work correctly. We put it in because I think it's a technology that, as we start improving it, maybe in the later stage in some years, we can double or triple the energy. Then suddenly you get to the point where you can do small trips without even using any other power than solar. We are not there yet."
A solar roof is only available on the top trim of the Ocean, the $68,000 Extreme trim, which has a movable glass roof with solar. The base Ocean has a fixed glass roof. The Ultra mid-trim has a movable glass roof called "sky roof."
The 2022 Hyundai Ioniq 5 midsize electric crossover has an optional solar panel that covers most of the roof and acts as a complimentary charging source to extend the car's 300-mile range with the 77.4-kWH long-range battery. Hyundai says it can add up to 1,240 miles a year in sunny locations.
As the technology evolves and becomes more efficient, solar power will become a factor, says Karim Habib, head of the Kia Global Design Center. Kia is sister brand to Hyundai, sharing a parent. Habib said he thinks it could become a staple for many companies in the future.
Tesla and Toyota are developing solar cars, as are some startups such as Aptera Motors, Lightyear One, and Sono Motors.
The 2023 Toyota bZ4X electric compact SUV, coming in 2022 with a range of about 250 miles, will offer an optional solar roof in Japan but it is unclear when that option will be available in North America. For customers in Japan, the panels will generate enough electricity to drive about 1,120 additional miles a year of free range, Toyota says.
Tesla showed solar panels on the roll-up, garage-style tonneau cover on the Tesla Cybertruck prototype in 2019 and Musk at that time said the option would be accompanied by fold-out solar wings. Production of the Cybertruck has been pushed back to late 2022 and drone footage of the truck testing shows it has undergone some design changes. It is not clear if solar panels are still part of the design.
Solar panels are a good idea, generally speaking, says Polestar head of design Maximilian Missoni even though the Precept concept does not have one. The Precept, which will go into production as the Polestar 5, has a long glass roof and no rear window—a camera provides a rear view. The problem with adding solar panels is you get an opaque view instead of a clear one, he says.
While he may not be completely sold on solar panels yet, Missoni thinks a glass roof is becoming an industry standard. The effect of designers like himself continuing to add them to concepts and production vehicles is that they have the power to make people want them. "We create a desire for something."
Missoni does not have a problem with glass roofs in EVs in hot climes, requiring the air conditioning to work harder. It is a balance between needing to feel good and enjoy the ride versus efficiency loss, he says. And glass can receive a UV coating.
Removable panels are also emerging as a trend. The Infinity roof on the 2022 GMC Hummer EV electric full-size pickup and the 2024 GMC Hummer EV SUV still to come, has four removable transparent roof panels. The 2022 Rivian R1T electric pickup has a fixed sunroof now but will add an optional removable roof in 2022. The Jeep Wrangler and the Ford Bronco have removable roofs, but they are not glass. And Corvettes have come and gone with targa tops.