How much solar power can a car produce?
An important question is just how much energy is available from solar power on a car, and does this deliver any meaningful range?
The Lightyear One is claimed to be the first solar powered production car. It has 5m2 of solar panels, which equates to about 925 W of solar. At a good location, if exposed to sunlight all day during a good day, this can deliver about 3.9 kWh of energy.
To put this in perspective lets look at how much charge this can give to a Tesla battery. The base Tesla model 3 has a 50 kWh battery. Therefore the solar energy available from the top surfaces of a car can only charge about 8% of this battery. This gives about 17 miles of range. Clearly on more traditional vehicles with larger batteries, solar on the car may not make a lot of sense. You’re simply much better off just hooking the car up to a much larger solar array to get some decent charge from solar.
So where are commercial solar vehicles heading? For solar powered vehicles to make any sense, many are much more energy efficient than traditional cars so that smaller batteries can achieve a much bigger range. And they must use solar as a range ‘booster’ rather than the primary charge. The other approach, being explored by Tesla, is to have fold-out arrays of panels that can generate a lot more power.
So which solar-powered cars are closest to commercial reality?
The Lightyear One is one of the solar powered cars that claims to be the world’s first solar powered production car.
The Lightyear One’s long, sleek body has been designed for maximum efficiency. It also features an electric motor at each wheel to minimise energy loss. the body has a long tail and covered rear wheels to minimise drag, and is very light.
The range of the One is claimed to be 725km. Lightyear claims that in ‘optimal conditions’, 12km can be added to the car’s range each hour, purely from sunlight. So about 70km over the day. Importantly the Lightyear One he One is not just powered by the sun – it can get around 507km of range from one hour of fast charging.
The Lightyear One pays for high efficiency in performance: it is rumoured to take 10 seconds to reach 100 km/h. Also, this futuristic technology comes at a price: about $185,000. It is due for production in 2021 and deposits are being taken on the company’s website.
The Aptera is another car claiming to be the world’s first production solar powered car. When Aptera began taking pre-orders last December, it sold out of its planned first batch of 330 vehicles in 24 hours. Almost 7,500 people have now put down deposits.
Aptera Motors has unveiled its latest 3 EVs that will offer ranges of up to 1600km and cost just $35,000 when deliveries begin towards the end of 2021.
The Aptera 3 comes with a 25kWh battery and a 100kW electric motor that drives the front wheels. Even with a battery half the size of the base model Tesla 3, the Aptera 3 (coincidence??) has a range of 402 km. If that’s not enough, the small start-up will sell a larger 40kWh (644km), 60kWh (966km) or a range-topping 100kWh battery pack that offers the headline 1600km range. With a fast charger, the car-maker claims it adds 800km in range every hour the Aptera is plugged in. And on a nice sunny day in a good climate, the solar panels can add 70 km of range in a day.
The light weight of the car , (Aptera 3 weighs in between 816kg and 998kg) enables even the 100kW version to hit 60mph (97km/h) in just 5.5 seconds, while the 150kW flagship hits the same benchmark in just 3.5sec.
Looking like a futuristic batmobile and with minimal space for two passengers, the Aptera takes efficiency to new heights. The vehicle’s body — curved at the nose, wide along the sides and tapered toward the trunk — is built like a small, sleek aircraft. This reduces drag. The Aptera’s undercarriage curves like a dolphin’s belly. This serves to reduce the drag that comes from the turbulent air between the vehicle and the ground. These features give the Aptera extremely low drag coefficients.
Toyota Corolla: 0.29
Tesla Model 3: 0.23
The Aptera also reduces drag by using tires with very low rolling resistance: more than 10 different tyres were trialled. They also used three wheels instead of four, eliminating one point where energy can be lost.
The Aptera is built with ultra-light carbon composites and fiberglass to minimise weight.
Energy efficiency is also a key feature. Inside the vehicle, heat is automatically removed while parked, lowering air conditioner load. Electronics are built with very low resistance wires. Ultra-efficient LEDs and low-power displays are used, with “sleep modes” for the main screen when not in use.
This car may not be the most practical but it is sure to turn heads!
German start-up Sono Motors unveiled its new solar-powered Sion early this year. Unlike the other Aptera and Lightyear, the Sion is a more traditional, family-oriented car. And a price tag of about $28,000 also keeps it in the range of a family budget.
Full specifications are listed on Sono’s website. With a 255km range and top speed of 140 km/h, and four-seater layout, the car is certainly practical. Up to 35 km per day of range can be produced by solar cells with cover the car.
Drivetrain: 120kW Motor
Trunk Volume: 650 l
CCS: 30 min
Type 2: 3.5 hrs
SchuKo: 13 hrs
Range: 255 kilometres according to WLTP standard
Solar Range: Up to 35km/day
Max. Speed: 140km/hr
Tow Bar: 750kg
One drawback: since the car is literally covered in solar cells, it only comes in one color: black.
Squad Mobility has just released the Squad solar-charging car.
Looking more like a golf cart than a car, the Squad is designed for urban mobility. The has a maximum speed of 45 km/h, carries two people and retails at $6,335. Depending on demand and local legislation an 80 km/h version is also available.
The car is built with “concentric European style cities” in mind, which “are not particularly designed for cars.” They are designed to be compact and easy to park
“Our solar-electric Squad can charge up to 9.000 km per year in a sunny country with its own 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 extra range is needed, it can be charged directly from the grid with an ordinary plug or portable batteries that come with the car.
Elon Musk announced that the new Tesla Cybertruck would be the first car from the company to offer solar panels as an option for extending range.
Musk claims the solar panels will have the capacity to add 15 miles per day to the car’s range. He says the average a person drives per day in the U.S. is 30 miles
Tesla are also considering adding “fold out solar wings” to increase the range of the Cybertruck even further — this could allow the car to double the added range from solar to up to 40 miles .
While the idea of solar powered cars sounds cool, the reality is there is only enough area on a car for solar to provide a limited amount of power. Futuristic super-sleek, super-light cars that minimise drag and maximise efficiency can extend the range from solar power. However these are expensive and may not be particularly practical.
More traditional, practical cars with solar power offer much more modest range from their solar panels. In urban environments, where the average travel distances are small, solar may contribute a significant portion of the cars total travel range. These cars are becoming very affordable.
With several solar powered production vehicles being released this year, how they perform in the market will be of great interest. The question will be is the extra expense really worth it?
The amount of energy available from solar panels on a car is limited. Depending on the vehicle, solar panels may give between 5 and 50 miles per day.
Several cars are now available via deposit, pending production in 2021. These include the Lightyear One, the Apteria and the Sion.
Yes. Solar panels will be an option on the Tesla Cybertruck. The panels will give a range of about 15 miles per day.
Yes. All solar powered cars can be charged using normal chargers. With the highly efficient cars, an advantage is that smaller batteries can give longer ranges, and can be charged much faster.