How does solar energy work?
Solar panels are composed of smaller units known as solar cells. The most common type of solar cell is made from silicon, which is the second most abundant element in the universe.
A solar cell has crystalline silicon sandwiched between two conductive layers. Each silicon atom is linked to its neighbor by four strong bonds. These bonds keep the electrons in their place and prevent any current from flowing. The key is that a silicon solar panel uses two layers of silicon.
Light can be described as the flow or movement of photons from the Sun. If one of these photons hits a silicon cell with enough energy, it can knock out an electron’s bond and leave a hole. Both the negatively charged electron and the location of a positively charged hole can now move freely. The electric field means that they can only move in one direction. The electron will be drawn to the negative side and the hole to the positive side. Thin metal fingers located at the top of each cell collect the mobile electrons. They then flow through an external circuit to do electrical work, such as powering a lightbulb.
