Solar Cell Diagram: Understanding How it Works

A solar cell, also known as a photovoltaic (PV) cell, is a semiconductor device that converts sunlight into usable electrical energy. The process begins with photons of light energy from the sun falling on the semiconductor junction, creating electron-hole pairs.

The displacement of free charge creates an electric current when a load is connected across the terminals. Holes pass to the P-region and electrons pass to the N-region. This phenomenon is known as the photovoltaic effect.

Solar cells typically consist of single crystal silicon P-n junctions. They are sensitive to photovoltaic effects, which enable them to convert sunlight into electricity. The resulting electric current can be used to power various devices, including operating water pumps for domestic and agricultural purposes.

The efficiency of solar cells is influenced by the band gap energy, which ranges from 1.12 eV to 2.3 eV. Materials with a smaller band gap energy are more effective at converting sunlight into electricity, as they can harness a larger number of photons from the solar spectrum.

In practice, silicon and gallium-based semiconductors are commonly used in the production of solar cells. These materials have high efficiency rates, with some modern solar panels boasting conversion rates as high as 25%.

The first practical solar cell was developed in 1954 using selenium (Se). Today, solar cells are used to power a wide range of applications, including remote and isolated locations, space stations, and artificial satellites.

When connected together, multiple solar cells form a solar panel. This setup enables the production of stronger currents under high potential difference. To minimize reflective losses from the surface, some solar panels are coated with a thin film of silicon monoxide (SiO).

In summary, solar cells are devices that convert sunlight into electricity through the photovoltaic effect. Understanding how they work is essential for harnessing this clean and renewable energy source.

Solar cell diagram