A city car prototype powered solely by solar power has been developed by six European companies.
The vehicle, which weighs less than 600kg, is designed specifically to meet the needs of city travellers 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 kilometre," 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.
Having been awarded €2.8m of funding, the recently concluded P-MOB project brought together several European companies and research institutions including Germany’s Siemens, Spain’s Mazel, Italy’s Fiat and Polimodel and UK’s Magnetomatics and the University of Sheffield.
"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.
The team focused on several shortcomings of existing electric vehicles and tried to perfect them – more efficient solar cells, e-motor and magnetic torque control, better accumulators and technologies to enable e-vehicles to put power back into the grid when they don’t use it.
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.