What are solar panels?

How do solar panels convert the Sun's energy into electricity?

Do solar panels wear out?


What are solar panels?

Solar panels are devices that convert light into electricity. They are called "solar" panels because most of the time, the most powerful source of light available is the Sun, called Sol by astronomers. Some scientists call them photovoltaics which means, basically, "light-electricity."


Figure from NASA's Jet Propulsion Laboratory Deep Space One Web Site: http://nmp.jpl.nasa.gov/ds1/

A solar panel is a collection of solar cells. Lots of small solar cells spread over a large area can work together to provide enough power to be useful. The more light that hits a cell, the more electricity it produces, so spacecraft are usually designed with solar panels that can always be pointed at the Sun even as the rest of the body of the spacecraft moves around, much as a tank turret can be aimed independently of where the tank is going.

How do solar panels convert the Sun's energy into electricity?

The solar panels are made of solar cells. A cell is a small disk of a semiconductor like silicon. They are attached by wire to a circuit. As light strikes the semiconductor, light is converted into electricity that flows through the circuit. As soon as the light is removed, the solar cell stops producing power.

Do solar panels wear out?

Solar panels are very hardy. Compared to alternative power sources, they wear out very slowly. Their effectiveness decreases around 1 to 2 percent a year.

From Principles of Operations website