Solar panels are a way of extracting electricity from sunlight. They produce electricity because photons – particles of light emitted by the sun that reach the surface of the earth – have the potential to knock electrons free from atoms. Once this free-flowing source of electrons is harnessed, a source of electricity will be created.
The magic of solar panels begins with what’s known as a photovoltaic cell. This is the smallest unit within what’s typically known as a solar panel. These individual cells are made up of two layers of semiconductive material. The most popular material used to construct these thin layers of conductivity is silicon.
The goal of these layers of silicon is to create an electric field, which works pretty similarly to a magnetic field. If the top layer of silicon is given a positive charge and the lower layer is given a negative charge, an electric field is created.
This is usually done by treating one layer of silicon with phosphorus to add extra electrons to the atoms within it. Since electrons are negatively charged, this causes the whole layer of silicon to have a negative electrical charge. The other layer of silicon is treated with the chemical boron, which has the effect of removing electrons from the silicon’s atoms. This infuses that layer of silicon with a positive charge.
After an electric field has been created, it’s ready for photons of sunlight to do the rest. Photons enter the electric field, and because of the photons’ unique properties, they knock loose electrons, which will then float freely unattached to an atom. The electric field created by the treated silicon layers then pushes these electrons out of the silicon junction towards specially built devices that collect this flow of electrical charges.
This results in a steady flow of electrons exiting the individual photovoltaic cells. It’s then a matter of collecting the electrons using conductive plates and then transferring them to wires to travel to a converter. A converter is needed because solar panels naturally generate direct current (DC) electricity, while most homes, appliances, and electronics are designed to run off alternating current (AC) electricity. Once this is done, the electricity is ready to be sent to a home, the power grid, or wherever it is needed.