How do solar PV panels work?

Solar PV (photovoltaic) panels generate electrical energy through the photovoltaic effect, which is the conversion of sunlight into electricity. Here's a step-by-step explanation of how it works:

1. Sunlight: Solar panels rely on sunlight as their energy source. When sunlight reaches the solar panels, it consists of photons (particles of light) carrying energy.

2. Semiconductor Material: The solar panels are made up of semiconductor materials, usually silicon. Silicon is chosen for its ability to absorb photons effectively.

3. Absorption of Photons: When photons strike the surface of the solar panel, they can be absorbed by the semiconductor material. This absorption transfers the energy from the photons to the electrons in the material.

4. Electron Excitation: The energy from absorbed photons causes some of the electrons in the semiconductor material to become "excited." These excited electrons move from their original positions in the atoms of the material to a higher energy level.

5. Electric Field: The solar panel is designed to create an electric field within the semiconductor material. This is achieved by adding impurities to the silicon, creating a region with an excess of electrons (n-type) and another region with a deficit of electrons (p-type). The junction between these regions is called a p-n junction.

6. Electron Flow: The electric field at the p-n junction causes the excited electrons to move towards the n-type region, where there is a higher concentration of electrons. This movement creates a flow of electrons, known as a current.

7. Conductors: Metal conductive plates are attached to the solar panel to collect the generated current. These conductors are usually made of aluminum or copper.

8. Electrical Energy: The collected current from multiple solar panels is combined and sent through an inverter, which converts the direct current (DC) produced by the panels into alternating current (AC) suitable for use in households or the power grid.

9. Distribution: The AC electricity produced by the solar panels can be used immediately to power electrical devices or fed into the electrical grid for distribution to other users. In some cases, excess electricity can be stored in batteries for later use.

By harnessing the photovoltaic effect, solar PV panels provide a renewable and sustainable source of electricity, converting sunlight directly into usable energy.