Photovoltaic cell

The photovoltaic cell, often referred to as a solar cell, is the basic building block of solar panels. It is a device that directly converts sunlight into electricity through a process known as the photovoltaic effect. This is the process that occurs when sunlight hits the semiconductor components in the panels. This energy transformation takes place at the level of the semiconductor material, usually silicon, which forms the main part of the photovoltaic cell.

The photovoltaic cell is the smallest visible part of the photovoltaic panel. It is followed by the PV module. Slightly larger is the solar panel, which consists of several modules.

• Semiconductor material: Most photovoltaic cells use silicon as the main material because of its availability and efficiency in converting light into electricity. Silicon can be in a monocrystalline, polycrystalline or amorphous state, with each form having different properties and efficiencies.
• The photovoltaic effect: When sunlight hits a photovoltaic cell, electron-level processes take place in the cell. The cells are made of 2 layers of semiconductors, one made up of atoms with a negative charge (they have a larger number of electrons). The other layer contains empty electron spaces or holes, which make this layer of the cell carry a positive electrical charge.  To increase the efficiency of the cell, the surface of the photovoltaic cell is often covered with an anti-reflective layer, which reduces the reflection of light and allows more light to reach the cell.
• Protective layer: To protect against external influences such as weather conditions or mechanical damage, the PV cell is covered with a durable protective layer.