How Solar Cars Work
This diagram gives a general idea how energy flows in a solar car. The sunlight hits the cells of the solar array, which produces an electrical current. The energy (current) can travel to the batteries for storage, go directly to the motor controller, or a combination of both. The energy sent to the controller is used to power the motor that turns the wheel and makes the car move.
Generally, if the car is in motion, the converted sunlight is delivered directly to the motor controller, but there are times when there is more energy coming from the array than the motor controller needs. When this happens, the extra energy gets stored in the batteries for later use.
When the solar array can't produce enough energy to drive the motor at the desired speed, the array's energy is supplemented with stored energy from the batteries. Of course, when the car is not in motion, all the energy from the solar array is stored in the batteries.