Aerodynamic drag, weight, and rolling resistance all influence the car's design. Solar energy is converted directly to electricity by the photovoltaic array. Electric energy is stored in batteries. Solar electricity can also go directly to the motor when the car is running. Modern electronic motor controllers smoothly and efficiently control power to the motor.
Speed control is by a normal accelerator pedal.
The latest in motor technology uses powerful rare-earth magnets and a brushless design. A 5 hp motor can weigh less than 5 kg. 5. The drive to wheels in advanced vehicles does not need a gearbox. Gear changing is done electronically in the motor. Solar Car Design A car's design is dominated by the vehicle performance demanded by the race.