7 companies that are leading the way for solar-powered cars

• The jury is still out on solar cars.
• Some say it is the future of mobility, while others claim it will never take off.
• Despite this, several notable firms are leading the charge on the technology.

Elon Musk said in 2017 at the National Governors Association meeting that “the least efficient place to put solar is on the car.” Now, Tesla's new Cybertruck offers the option to add solar panels for more range.

Either way, the naysayers aren't stopping big automakers and startups from developing the technology. There are some ideas where the payoff for success would be so huge that you have to try. 

1. Blending urban mobility and solar energy

Squad Mobility has just released the Squad solar-charging car. It is a car that uses solar's limitations as its strength.

Focused on urban mobility, the car reaches a maximum of 28 mph (45 kph), carries two people, and retails at €5,000 ($5,460). An 80 km/h version is also available depending on demand and local legislation.

The car is built with "concentric European style cities" in mind, which "are not particularly designed for cars."

Moreover, the cars are designed to be compact and easy to park, so they can spend most of their time soaking in the sun's energy.

“Our solar-electric Squad can charge up to 9.000 km per year in a sunny country with its solar roof, making it completely emission-free for most users driving circa 30 km or 1 hour per day for 300 days a year in an urban environment," Robert Hoevers, Squad Mobility CEO said in a press release.

If the extra range is needed, it can be charged directly from the grid with an ordinary plug or portable batteries from the Squad car.

2. The "world's first long-range solar car"

Dutch startup Light Year is producing a prototype for the first car capable of driving long distances powered by the Sun.

The car, called Lightyear One, has a roof and hood comprising five square meters of integrated solar cells.

The solar panels are encased in safety glass, "so strong that a fully-grown adult can [safely] walk on them," the company claims.

The car is made of strong but lightweight materials, allowing it the longest range possible. The company says this enables the car to have a range of 725 km (WLTP). Light Year says its car uses 83 Wh/km (WLTP) and accelerates from 0-100 in ten seconds.

The Lightyear One's solar array adds 7.5 miles (12 km) of range per hour when in the sun.

3. An auto giant joins the game

Hyundai has joined the relatively new solar car industry with its new version of its hybrid car, Sonata. 

The Korean car manufacturer says that between 30 and 60 percent of the vehicle's battery can be recharged by its solar panels.

Unlike other car companies on this list, Hyundai openly states that its solar roof system "plays a supporting role" in its hybrid engine. Perhaps due to the fact that this solar car comes from an established automaker, the car has been criticized for its lacking technological prowess.

As Forbes points out, Hyundai's car must park in the sun constantly to only give 2 miles (3.2 km) of power per day.

4. A sun-seeking vehicle

Plants are "heliotropic," meaning they move toward sunlight to get the energy they need. Now, your car can do the same thing.

One of the main criticisms of solar cars is that vehicles are typically kept in garages and aren't an ideal place for integrating solar panels. The Stella Ersa self-driving car is programmed to drive into the sun anytime power runs low.

It isn't just a solar-powered car, however. The company says the Stella Ersa it is "a charging station on wheels."

Innovations in charging — specifically bidirectional charging — mean cars can store energy and transfer it to the grid, other cars, and into battery packs in self-sustainable homes.

5. A car that charges itself

Sion is a hybrid electric vehicle made by German startup Sono Motors that charges itself using solar energy. The 248 solar cells integrated into its body mean it can be self-sufficient in driving over short distances.

The car can go up to 155 miles (249 km) on a single charge and adds around 21 miles (33 km) of charge per day via its solar panels. What's more, Somo Motors uses 100% renewable energy sources for the car's components and building process. 

The car is a part of Sono Motors' plans to make vehicles to reduce CO2 emissions worldwide. The Sion's battery was built with reduced cobalt content to make it sustainable. At the time of writing, however. Sono Motors are currently looking for potential investors to buy the Sion program.

6. Building a car that can "run forever"

In September, news came out that Toyota Motor Corp., Sharp Corp., and New Energy and Industrial Technology Development Organization of Japan, or NEDO, have teamed up to develop a Prius that, in theory, could run forever without fuel or conventional electrical charging - the answer, they say, is solar power.

“The solar car’s advantage is that — while it can’t drive for a long range — it’s independent of charging facilities,” Koji Makino, a project manager at Toyota, told Bloomberg.

The solar cells being used by Toyota, Sharp, and NEDO are only about 0.03 mm thick. This means more solar panels can be more easily placed on a car's surfaces, including its curvy parts on the roof and hood.

The solar panels for the prototype are said to convert sunlight at an efficiency level of more than 34% — the market standard is 20%.

7. Cybertruck goes solar

Elon Musk confirmed on Twitter last Friday that the new Tesla Cybertruck would be the first car from the company to offer solar panels as an option for extending range. The price for adding these solar panels to the vehicle has not yet been released.

In the past, Tesla has shunned the use of solar panels in its cars, the CEO saying the method lacks efficiency. It seems that the work of competitors may just have convinced Musk and the engineers at Tesla. 

Musk claims the solar panels can add 15 miles (24 km) per day to the car's range. He says the average a person drives per day in the U.S. is 30 miles (48 km).

What's more, the Tesla founder wrote about adding "fold-out solar wings" to increase the range of the Cybertruck even further — he said they would allow the car to double the added range from solar to up to 40 miles (64 km). Solar wings on a car might not seem practical, but these ideas show that Tesla changed its tact on solar cars and the company is taking the technology seriously.

While solar cars might not be on the verge of overturning the auto industry, it's the promise of forming part of a wider network of self-sufficient energy consumption that makes them such a tantalizing proposition. The technology has its critics, but we can't wait to see how solar-powered cars develop and whether they deliver on their enormous promise. 

And that is your lot for today.

While most of these models are yet to enter the general market, it is clear that significant progress is being made in the industry. Time and tide will tell when you can get your hands on one.