Be it in calculators, cars, road signs, or satellites the concepts of using photovoltaic power is constantly gaining limelight in the current times. It is not as alien as it was in 1958 when only the electrical systems of satellites expected to get charged from the solar energy. Now the world knows that if the sun is glowing bright, it is possible to generate about 1,000 watts of energy per square meter which can be used in a number of constructive ways. The solar revolution is thus strong in the current world.
Concept of Solar Panels
The best way of collecting and using the maximum of sun’s energy is through solar panels which are made up of numerous solar cells which are linked to one another. Each of the solar cells helps in creating electricity. It is now a common site to see roofs and road signs having solar panels to either light up the house or roads. In the current times even the automobile industry is coming with cars with solar panels on their roof so as to encourage the use of clean and renewable fuel rather than having a complete dependency on fossil fuels which are both non renewable and also create pollution.
How Does the Solar Panel Work?
The working of solar panel can be best explained by saying that when photons which are light particles strike electrons present in the solar cells and make them move, it creates a flow of electricity. The solar cells which are inside the solar panels and are also known as photovoltaic cells are made of semi-conductor material which is mainly silicon. When light falls on these cells, a part of it is absorbed by the semiconductor silicon and the energy which is there inside the light is transferred to silicon. It is these energy particles, also known as photons, which react with the electrons within the cell and generate electricity.
In order to make these cells works, it requires to create an electric field with two opposite polls. Usually within one photovoltaic cell there are one or more electric fields. It is for this reason that the silicon of the cells is doped with other materials so that a positive and negative field can get created respectively in each cell. These additional materials are usually phosphorus on one half and boron on the other. While phosphorus increases the number of electrons and gives a negative charge to its side, boron on the other end keeps the number of electrons less and thus creates a positive end. This set up creates a combination of positive and negative charge and thus an electric field gets created.
When sunlight falls on these cells, the photon in the sunlight knocks the electrons within the cell and they are set free. The electron is pushed out of the silicon sandwich by the electric field and thus they become free to flow. There are also some additional elements within the cell which help in turning the electrons in useful power. These additional elements include metal conductor plates which not only collect the electrons but also convert them into wires so that electrons can develop a flow as is done with any other source of electricity. It is these metal contacts on the top and bottom which help in drawing the current externally. It is this current in addition to the voltage of the cell which is created from the electric field(s) that makes up the total power of a single solar cell.
While solar cells and panels are one sort of apparatus which help in using the energy of the sun, there are other technologies too which help in collecting, concentrating, and using solar power for the same usages like generating electricity and providing warmth or heating of water.