Solar cells, also known as photovoltaic (PV) cells, are non-mechanical devices that directly convert sunlight into electricity through a process called the photovoltaic effect. These cells are predominantly made from silicon, a semiconductor capable of absorbing sunlight and converting it into electrical energy.
In a typical solar cell, there are two layers of silicon: one treated with phosphorus to create a positive (P-type) side, and the other with boron to create a negative (N-type) side. Metal conductive plates are placed on each layer, and the junction between these layers generates an electric field.
When photons from sunlight strike the solar cell, they knock electrons loose from their atoms. These liberated electrons can then flow through the conductive plates, creating an electric current that flows through the circuit. This current moves in one direction, from the negative to the positive side, generating electricity.
Each solar cell typically has a capacity of around 3 to 4 watts peak (Wp). To increase output, multiple cells are connected together to form a PV panel. Several of these panels are then connected in series and parallel configurations to achieve the desired output rating.
The electricity generated by these interconnected panels is in the form of DC (Direct Current). To make this electricity usable for local consumption, it is passed through an inverter that converts it into AC (Alternating Current). Depending on the specific system setup, this AC electricity can be used directly by local loads, stored in batteries for later use, or fed into the grid.
