Photovoltaic Cells

What is photovoltaic effect?

Photovoltaic effect is defined as the phenomenon in which the incidence of light upon the junction of two dissimilar materials, as a metal and a semiconductor, induces the generation of an electromotive force. Simply put, photovoltaic effect is the creation of electric current in a material upon exposure to light and is an electro-chemical phenomenon. Having no moving parts – like turbines etc. which are typical of other forms of electricity production- is a unique advantage of photovoltaic power generation.

The most common material used to make solar PV cells is Silicon because it shares some of the properties of metals and some of those of an electrical insulator. Photovoltaic cells consist of a positive laver and a negative layer of this material. Let’s take a closer look at what happens when the sun shines onto a solar cell.

Sunlight consists of little particles of energy called photons. When this energy in sunlight strikes the silicon based solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity.