How Do Solar Panels Work?

This page contains diagrams and information on the basic operation of a modern solar panel.

As more people become aware of the problems to the global environment with carbon fuel based electricity production clean alternatives such as solar panels are becoming ever more popular. Many people wonder how a solar panel works, so we've answered it the best we can with diagrams and descriptions below.    

When the suns solar energy rays hit the solar panel's cells, direct current (DC) flows through an inverter, converting the (DC) current to alternating current (AC).  AC power can then flow directly into a device or building (if required), or into backup batteries to be used later( if the system has them) , or to a utilities company hooked to a grid.(national or local supply).

The solar cells you would have seen on satellites,caculaters etc are photovoltaic cells or modules (modules are a collection of solar cells electrically connected and joined together in one frame). Photovoltaics, (photo = light, voltaic = electricity), convert the energy of sunlight directly into electricity. Originally expensive and only used in space, photovoltaics are now finding many applications on countless devices,buildings etc were ever remote or free and environmentally sustainable produced electricity is required. 

Photovoltaic (PV) cells are made of special materials called semiconductors like silicon, which is currently the most commonly used. Basically, when light shines on the solar cell a percentage of this solar energy is absorbed into the semiconductor material. This energy now inside the semiconductor knocks electrons loose allowing them to flow freely. PV cells also all have one or more electric fields that  force electrons freed by light absorption to flow in a certain direction. This flow of electrons is an electrical current. Metal contacts on the top and bottom of the PV cell draw that current off to use to power external electrical products such as lights, calculators etc. This current ,combined with the cell's voltage (which is a result of its built-in electric field or fields),determines the power (or wattage) that the solar cell can produce.