There are several electric cars with solar panels available today — some recharge the smaller 12-volt battery that runs your air conditioning, while others can top you up with a few miles of electric range — but at this time, no commercially available solar panels are capable of fully powering an electric vehicle.
That said, reports Edmunds, this concept isn't as far away as it might've been 20 years ago. Here's why:
In theory, the dream of solar energy is an exciting one. You put a few square meters of solar panels somewhere that gets a reasonable amount of exposure to that big, bright ball in the sky and, hey, you've got free limitless electricity to power your car, house or business.
But in practice, many hurdles must be overcome for an electric car to run fully on solar energy.
Which electric cars have solar panels?
Fisker Ocean
Fisker's Ocean promises a lot, and, according to Edmunds' testing, delivers very little, but one thing that it does have is a solar roof on its most expensive Ocean Extreme trim. Fisker says this roof, with its distinctive pattern, can generate up to 1,500 miles of range per year or up to 2,000 miles in ideal conditions. That's just over 4 miles of range per day on the low end and nearly 5.5 miles per day on the high end.
Fisker Karma/Karma Revero
Much like his latest efforts with the Ocean SUV, Henrik Fisker's previous automotive experiment shot for the moon when it came to trying to change the automotive landscape. The Karma was a plug-in hybrid with an impossibly long, low and lean body with a small solar roof. As with other small solar roofs, it didn't do much — offering just 200 watts of charging, it would take upward of a month to charge the car's 20-kWh main battery under average conditions.
Toyota Prius Prime
The current generation Prius Prime has a neat trick up its sleeve if you tick the options boxes just right. For about $600 (or as part of other packages) you can get a solar panel roof, which replaces the glass roof of the standard car. This roof will not only help to charge the Prius' main battery, but it can also power accessories such as the air conditioning while you're driving provided there's enough sun to do so. While it may not add much range to your EV-only driving, it is priced low enough to consider adding.
Hyundai Ioniq 5
Some trims of the Hyundai Ioniq 5 in international markets have solar panels built into their roof structures. Hyundai estimates that, under ideal conditions, this roof adds around 3 miles of range per a day. That might not seem like much on a car with an EPA-rated range of up to 303 miles, but it's more than the roof would otherwise be doing without it. If your commute is only a few miles, there's a chance you'll be spending even less time plugged in. The panels can also combat any minor drain or self-discharge issues if the car just sits parked.
Nissan Leaf (first generation)
Nissan's Leaf was the first truly mass-market electric car for American buyers. Some of you might not remember that it had a small solar panel built into its roof to help ensure that its 12-volt accessory battery was always topped up. In practice, it may not have been that effective because many owners took to websites like Reddit to complain after finding their Leaf's 12-volt battery dead.
Hyundai Sonata Hybrid (seventh generation)
Starting in 2019 with its radically styled seventh-generation Sonata, Hyundai decided that it was time to go all in on efficiency and added a neat little 204-watt solar panel to the roof of the Limited trim of the Sonata Hybrid. As with other modern solar roof setups, it can power both the main battery and the 12-volt battery.
Powering the whole car
The first big hurdle with powering a car with solar energy is efficiency.
While the sun hits the atmosphere of the Earth with a whopping 1.31 kilowatts per square meter (a rate known as the solar constant), a huge portion of that energy has been lost by the time it gets down to us on the surface.
The solar energy ends up at about 340 kilowatts per square meter on the surface, averaged over the whole planet.
For context, if you had a 1,000-watt microwave oven, you'd need just shy of three hours of solar energy from one square meter of surface area to run it. It seems simple enough, but it gets more complicated from here.
The most common way of capturing solar energy is to use solar panels. There are other ways, but they're not really designed for consumer-level use. Solar panels aren't perfectly efficient technology, as much of the energy collected is lost to heat. The most efficient panels today generate power from about 22.8% of the sunlight it collects.
According to EnergySage, you will need about seven to 12 solar panels to charge an electric vehicle at home.
Given that each panel is roughly 5 by 3 feet, there simply isn't enough solar power being generated — or real estate on the vehicle for enough panels — to provide the energy needed to fully power a moving vehicle.
Where solar makes sense
While your average five-passenger electric car with plenty of range may not make sense as a solar-powered vehicle, there are some situations where solar is a great way to go.
Take microcars, for example. They aren't especially popular in the U.S., but they make a lot of sense for young drivers in famously cramped European cities.
You also have the golf cart-like Squad solar-powered car by Squad Mobility. This little car features an aluminum exo-frame, tires that stick out in front of and behind the body to reduce parking dings, swappable batteries, and enough solar power on the roof to add up to 18.6 miles (29.9 km) of range in ideal conditions. It can do so thanks to its lightweight and low top speed, which is why it can be driven by people as young as 16 in the Netherlands, where Squad is based.
Future vehicles promising solar driving
Just because today's technology doesn't support a vehicle powered exclusively by the sun doesn't mean that tomorrow's technology won't, or even that companies aren't trying to find ways to make it work now.
Two big names making big solar claims are Aptera and Lightyear:
Aptera has been working on its odd insect-like three-wheeled EV for over a decade and has been inching toward a production-ready vehicle.
Lightyear, meanwhile, has touted a cool-looking and expensive four-wheeled solar-powered EV called the Lightyear 0, but it canceled production in favor of a cheaper, less extravagant version called the Lightyear Two.
Even big companies like Mercedes-Benz are testing the waters of solar power with prototypes like the Vision EQXX, which debuted back in 2022.
Not only does the EQXX look super futuristic and cool, but it has a target efficiency of better than 10 kilowatt-hours per mile, leading to a potential 1,000-mile (1,609-km) total range.
A company with Mercedes' resources and engineering prowess seems a lot more likely to figure out the solar car situation and put it into production, so this is one to keep an eye on.
This article was originally published by Stacker and was republished with permission.
