How Does a Solar Car Work?

by Contributing Writer

Solar Basics

Like other solar-powered devices, a solar car gets its power directly from the sun. Solar energy radiates from the sun and is collected by a solar panel mounted on the vehicle. The solar power can be directed to the motor or may be stored in a battery, depending on the design of the car. Individual solar cells or one larger solar panel can be mounted on the vehicle. When sunlight hits the solar panels, photons (or light particles) push on the electrons inside the panel, and the electrons are moved from one layer of solar cells to another. The movement between layers of solar cells creates an electrical current across the metal of the solar cells. Most solar-power cars use silicon solar cells.

Car Design

Factors like drag, weight and rolling resistance inhibit the performance of a solar-powered vehicle in comparison to conventional cars (i.e. gasoline, bio-fuel and hybrid designs). To lighten the frame and chassis of a solar car, individual solar cells can be used in place of a large solar panel. Hobbyists and car enthusiasts can purchase solar cells from ASE Americas or Siemens (see Resources below).

Components

The key component in a solar car is the photovoltaic array, which converts solar power into electricity. The electric energy goes directly to the motor when the car is being driven. However, a battery stores solar power in the form of chemical energy when the motor is turned off. Power to the motor is managed by motor controllers. An accelerator tells the motor controllers how fast the motor should rotate. Most solar cars have a small motor constructed of strong magnets. Japanese solar power cars have designs that include a natural magnet and an electromagnet inside of the motor, thus converting solar power into electromagnetic power. It is not necessary to manually shift gears in a solar-powered car, as the electronic motor handles all transmission automatically, and power trackers are installed to adjust solar power voltage to the motor's voltage requirements.