Solar panels, also known as photovoltaic (PV) panels, convert sunlight into usable electricity through a process called the photovoltaic effect. Here's a simplified explanation of how solar panels work:
1. Photons Absorption: When sunlight (which is composed of tiny packets of energy called photons) strikes the surface of a solar panel, the solar cells within the panel absorb the photons.
2. Semiconductor Material: Solar panels are made up of multiple layers of semiconductor material, typically silicon. Silicon is chosen because of its properties that enable it to conduct electricity.
3. Electron Excitation: When photons are absorbed by the silicon atoms in the solar cells, the energy from the photons excites the electrons in the atoms, causing them to break free from their atoms.
4. Electric Field: The silicon material is specially treated during the manufacturing process to create a built-in electric field. This electric field exists within the solar cell, causing the free electrons to be pushed in a specific direction.
5. Electron Flow: The electric field forces the free electrons to move in a uniform direction, creating a flow of electric current. This flow of electrons can be harnessed to generate electricity.
6. Metal Contacts: Metal conductive plates on the top and bottom of the solar cells collect the electrons and transfer them out of the solar panel as direct current (DC) electricity.
7. Wiring and Output: The DC electricity generated by the solar panel is sent through wiring to an inverter. The inverter converts the DC electricity into alternating current (AC), which is the type of electricity used in homes and businesses. The AC electricity can then be used to power electrical devices or fed into the electrical grid.
8. Grid Connection (if applicable): In grid-connected systems, excess electricity generated by the solar panels can be sent back to the electrical grid. This allows homeowners or businesses to receive credits or payments for the surplus electricity they contribute.
It's important to note that a solar panel generates electricity only when sunlight is available. Therefore, the electricity production is directly related to the amount of sunlight received, which can vary based on factors such as time of day, weather conditions, and geographic location.