Solar Cell

A solar cell is an electrical device that, through the photovoltaic effect, converts the energy of light directly into electricity. The photovoltaic effect is both a physical and chemical phenomenon.

When exposed to light, it is a type of photoelectric cell, which is defined as a device whose electrical characteristics such as current, voltage, or resistance change as a result of the exposure. Solar cells, also known as photovoltaic modules or solar panels, are the building blocks of photovoltaic modules.

Overview of Solar Cells 

It makes no difference whether the solar cells are powered by sunlight or artificial light; they are referred to as photovoltaic. The photodetector (for example, infrared detectors) is used to detect light or other electromagnetic radiation in the visible range, as well as to measure the intensity of light.

In many cases, solar cells are bundled together to form larger units known as solar modules, which are in turn combined to form even larger units known as solar panels.

As with batteries, solar panels contain cells that are designed to generate electricity. However; unlike batteries, solar panels contain cells that generate electricity by capturing sunlight rather than by converting chemicals into electricity.

Working of solar cell

A solar cell is made up of two layers of silicon: n-type silicon and p-type silicon. In order to generate electricity, it makes use of sunlight in order to cause electrons to hop across the junction between the various flavours of silicon:

Whenever sunlight strikes the cell’s upper surface, photons (light particles) are emitted and bombard the surface.Photons (yellow blobs) are charged particles that carry energy down through the cell.The photons give up their energy to electrons (green blobs) in the lower, p-type layer, which is where the photons are absorbed.With this energy, the electrons are able to jump across the barrier into the upper n-type layer and escape into the circuit below.The electrons, as they circulate around the circuit, cause the lamp to illuminate.Solar Cells Come in a Variety of Shapes and Sizes

Types of solar cell

First-generation solar cells are made from wafers of crystalline silicon (abbreviated c-Si), which are sliced from large ingots and grown in ultra-clean laboratories over a period of several months. The ingots are either single crystals (monocrystalline or mono-Si) or contain multiple crystals (polycrystalline or poly-Si) (polycrystalline, multi-Si or poly c-Si).

Secondly, second-generation solar cells are wafers that are typically only a fraction of a millimetre thick (about 200 micrometres, or 200 microns, or so) and have a relatively thin thickness. These cells are, however, absolute slabs when compared to second-generation cells, also known as thin-film solar cells or thin-film photovoltaics because of their thinness, which is approximately 100 times thinner (several micrometres or millionths of a metre deep). Amorphous silicon (a-Si), in which atoms are arranged randomly rather than precisely ordered in a regular crystalline structure) is still used in the majority of transistors, but some transistors are now made of other materials, including cadmium-telluride and copper indium gallium diselenide.

Second and third generation solar cells are being replaced by third generation solar cells, which combine the best characteristics of the first and second generation cells. In the same way as first-generation cells, they promise to achieve relatively high efficiencies (30 percent or more). Second-generation cells are more likely to be constructed from materials other than “simple” silicon, including amorphous silicon, organic polymers, and perovskite crystals, and to have multiple junctions, as are first-generation cells.

CONCLUSION

We discussed working , types & about solar cell’s key device that converts the light energy into the electrical energy in photovoltaic energy conversion. In most cases, semiconductor is used for solar cell material. The energy conversion consists of absorption of light (photon) energy producing electron–hole pairs in a semiconductor and charge carrier separation. A p–n junction is used for charge carrier separation in most cases. It is important to learn the basic properties of semiconductor and the principle of conventional p–n junction solar cell to understand not only the conventional solar cell but also the new type of solar cell