Generally speaking, I don’t think solar-powered cars are very practical. They are fun and do highlight how far we’ve come. They may help to advance certain electric car technologies and designs. However, except for certain niche situations (like a hospital car for rural Zimbabwe), they have serious limitations.
For one, solar panels aren’t cheap — risking their destruction or damage in a car accident doesn’t seem wise. Secondly, the sun doesn’t shine 24/7. To maximize the power you can get out of an electric car + solar panel system, it’s generally best to put the solar panels somewhere that’s never shaded by anything but the clouds or an eclipse (i.e., not on top of a car) and then charge up the electric car when it’s parked nearby (which is likely to be for many hours a day).
So, I was a little surprised to stumble across this story about a city car prototype that is only powered by solar power. The car is apparently being developed by 6 European companies, and it has been awarded €2.8 million in funding. Tehran Times writes:
The vehicle, which weighs less than 600kg, is designed specifically to meet the needs of city travelers in sunny south-European regions, and has a maximum speed of 100km/h and a range of 20km.
The “vehicle’s performance met our expectations for the design. It showed very high stability on small radius curves and had an average energy consumption of around 80 Watt-hours per kilometer,” said Pietro Perlo, CEO of Interactive Fully Electrical Vehicles (IFEVS), who has coordinated the project. The vehicle has been tested last month at Fiat’s testing track in Turin.
The “design has met the highest safety ranking, a low footprint and extremely low energy consumption, making the vehicle ideal for most people’s needs in cities as well as suburban roads,” Perlo said.
Here’s more from the Tehran Times article:
The integrated ICT-based control systems used in the car allow two motors and two differentials operating at the same time. The vehicle’s front and rear axles are thus independent, providing effective four-wheel drive, as well as variation of the torque ratio, depending on driving conditions.
“Our vehicle is the first with a two-motor powertrain with one motor per axle,” Perlo said.
Such a solution, the researchers believe, increases vehicle control on small radius curves, improves adherence on wet and icy roads, and provides faster acceleration without drawing more power. Similarly to passenger aircraft, if one motor fails the other will enable the journey to continue without compromising safety.
At the same time, the team has been working on the design elements to boost the efficiency of the solely solar-powered city car. They looked at several building blocks, including aerodynamic design to reduce drag and lightweight, low-cost but safe bodies.
“We have two doors on one side only, ensuring a high degree of safety, better ergonomics and reduced complexity with extremely low aerodynamic drag – around 30 per cent lower than other vehicles of the same dimensions,” said Perlo.
The car’s smart photovoltaic panels with smart diodes and self-adapting electronics minimise loss of energy caused by imperfect light conditions or a single malfunctioning cell. If the need arises and the sun is simply not enough, the car can be plugged into a regular socket and charged in the same manner as conventional electric cars.
Interesting… what do you think?