The world is blessed with abundant sunlight that can be converted to solar energy. We currently use solar energy in our homes, roads, and offices, what if we do the same with our cars? 70% percent of cars globally are driven less than 3 hours daily. With 12 hours of daily sunshine, imagine if our cars could tap energy from the sun at no cost, no emission, and no plugging or filling up tanks. This is the dream behind solar cars.
In this section, we will examine some of the best solar-powered cars on our roads, and how reliable they are by looking at some advantages of solar powered cars.
How Do Solar Cars work?
A solar car is a type of electric vehicle (EV) that uses inbuilt solar cells to generate power partly or fully via sunlight. As a form of EV, Solar cars also contain rechargeable batteries that store the energy generated by solar cells. To have sufficient energy, some solar cars come with additional solar cells that can be plugged into an external power source to supplement the solar power generated from direct sunlight.
Solar cells are built with photovoltaic cells (PV) that convert sunlight into electricity. These PV cells are made of semiconductors like silicon and alloys of indium. When sunlight radiation strikes the PV cells, electrons are released thus creating electric currents. These solar cells are placed on the car’s roof, trunk, hood, wheel cover, and other exterior parts for direct contact with sunlight
Some solar vehicles can also generate energy from regenerative braking ( energy derived from converting a moving vehicle’s kinetic energy into a form that can be stored for future or immediate use by the vehicle). Regenerative braking enables solar cars to be energy efficient to maximize the limited amount of solar energy they can derive from sunlight.
Solar Car vs Electric Cars
Whereas a normal electric vehicle would require regular charging, with a solar-powered car, you can drive for months without charging as the solar capability gives it 3x – 5x less charging. Solar Powered Electric cars have an integrated solar panel that charges the battery whether at rest or in motion, thereby extending the stored charge in the battery.
With a solar panel chargeable electric car, you don’t need to charge your battery for short or medium trips when traveling longer trips, you could drive more than 500 miles before you stop for a battery charge.
Let’s consider some of the benefits and demerits of solar cars.
The Disadvantages of Solar Cars:
Limited Surface to Generate Enough Energy:
Every vehicle needs to generate enough energy to power its engine. Solar cars rely on solar energy; hence they need large a surface area where the solar panels can be placed to generate sufficient electricity. To drive a car at an average power of say 30KW, the car would need about 120 square meters of direct solar panel surface in bright sunny weather conditions.
With limited square meters of space on car surfaces, there is a limitation to the number of solar panels a typical car could carry.
To address this challenge, solar cars have built-in batteries that store the solar-generated energy to provide sufficient power for each journey. In addition, solar powered cars also come with extra solar cells that can be plugged into external power sources as supplements to the solar energy generated directly from sunlight.
High Production Cost of Solar Panels:
Highly efficient solar panels that are capable of generating sufficient energy to power a car over a long distance are difficult and expensive to produce. Most solar panels in the market have an efficiency rate of about 15%, with 45% being the highest panels on the market. The Stella Terra team was recently reported to have successfully tested a 97% bespoke converter. The Bespoke marks a significant breakthrough in solar panel technology that could revolutionize the solar car industry.
High Acquisition Cost:
Solar-powered cars are relatively more expensive to acquire than their battery-powered EVs and internal combustion counterparts. One of the first models – Lightyear has a retail value of about $50,000 when it comes into full production.
Few Solar Cars Manufacturers:
There are only a few solar car manufacturers with many still in the development stage. The few successes recorded are in the form of Hybrid solar electric cars.
Benefits of Solar Cars
Solar car comes with more benefits
- Eliminates the need for fossil fuels thereby achieving an eco-friendly sustainable mobility
- Solar cars run on clean energy and do not generate pollution like carbon dioxide.
- Solar cars provide an alternative to traveling long distances as your car battery can get changed by the sunlight while you enjoy your travel.
- The long useful life span of the Photovoltaic panel of about 30 years.
- Cheap maintenance cost as they have fewer parts requiring frequent maintenance.
- Cheap operational costs as you do not need to fill up tanks or plug in to charge all the time.
- Less strain on the existing power grid which is already under pressure due to the increasing demand for charging stations for electric cars.
Solar Car Challenge and Success
There are several challenges around the world to design, build, test, and race solar vehicles in long-distance car competition events with participation from individuals, teams from colleges and universities, and companies. Some of the common solar car challenges include
- -America Solar Challenge
- -World Solar Challenge
- -United Solar Challenge.
Solar Car Success Story
Are there solar powered cars on our roads? Yes. The solar car challenges and investments have brought about success with some solar hybrid cars already running on our street. Some of the successes recorded include
- Stella Solar Car
- The Lightyear 0.
- Tesla Cybertruck (Solar Car Tesla)
- Prius PHEV Solar
- Lucid Air from the California company
- Spanish prototype, the Ecovelo Mö
- Aptera Solar electric vehicle
- Sonor Sion
The Stella Solar-Powered Car
The Stella Solar car has been reported as the world’s first solar-powered car capable of driving long distances without recharging after it completed a 620-mile test drive. The Stella Solar car designed by students of Eindhoven University of Technology was successfully tested recently in a 620-mile road trip across Morocco and the Sahara desert in Africa. According to the Guardian, the Stella Solar vehicle which weighs 1.2 tonnes completed the journey across a challenging landscape with its multiple solar panels on its solar roof and traveling at a top speed of 145kmph/90 miles per hour.
The Stella Solar car contains a rechargeable lithium battery which stores solar energy that allows it to drive on in less sunny climates. The car has an efficient converter (97%) that allows PVs to turn sunlight into electric charge. There is presently no information on the production cost of this car.
The Lightyear 0.
One of my favourite solar-powered electric car manufacturers is Lightyear One which can travel 500 miles at full charge. According to Lightyear, the current starting price of Lightyear 0. is expected to be about $40,000.
The car production company Atlas Technologies B.V. was however reported to have halted vehicle production in 2023.
Solar Car Tesla
The Tesla Pickup truck – Cybertruck comes with optional rooftop solar panels that can add an extra 15 miles of travel per day was disclosed by Musk during a recent Joe Rogan podcast. The 6000-pound vehicle is also expected to come with an optional full bulletproof including the window glasses.
The surface area limitation of cars was also stated as one of the major challenges to building solar powered cars. The cyber truck comes with a 100KWh battery pack similar to other Tesla cars Model S and X. The vehicle is expected to compete with other electric pickup trucks like the Ford F-150 Lightning and Rivian R1T which comes with I31KWH and 135KWH battery pack capacity respectively.
Sonor Sion
The Sonor Sion Solar car is one of the most anticipated solar cars with over 20,000 reservations. Sono Motors produces a variety of solar vehicles like solar-powered buses and solar refrigerated trailers. The company initially planned to produce about 250000 units annually starting from July 2023 at an average $28000 selling price. Sono Motors recently posted on its website its plan to terminate the Sion program and sell the asset to a third-party firm.
Aptera Solar electric vehicle
The Aptera is a three wheeled, two seat vehicle still under development by Aptera Motors, a company being crowd funded. The vehicle makes use og lightweight carbon fiber, built in solar panel, and fiberglass composite materials. The vehicles Gamma prototype was unveiled in December 2022 featuring an improved legroom and head, as well as a touch screen center console. The vehicle is still under development but currently has about 40,000 order reservations as of September 2023.
