The principles of solar electricity

A solar panel generates electricity using the ‘photovoltaic effect, a phenomenon discovered in the early 19th Century, when it was observed that certain materials produced an electric current when exposed to light.

To create this effect, two layers of a semi-conducting material have to be combined. One layer has to have a depleted number of electrons. When exposed to sunlight, some of the photons are absorbed by the material which excites the electrons, causing some of them to ‘jump’ from one layer to the other. As the electrons move from one layer to another, a small electrical current is generated.

The semi-conducting material used to build a solar cell is silicon. Very thin wafers of silicon are cut and polished. Some of these wafers are then ‘doped’ to contaminate them, thereby creating an electron imbalance in these wafers.

The wafers are then aligned together to make a solar cell. Conductive metal strips are attached to the cells to take the electrical current.

When a photon hit the solar cell, it can do one of three things: it can be absorbed by the cell, be reflected off the cell or pass straight through the cell.

If a photon is absorbed by the silicon, this causes some of the electrons to ‘jump’ from one layer to another. An electrical circuit is made as the electrons move from one layer to another, creating an electrical current.

The more photons (i.e. the greater intensity of light) that are absorbed by the solar cell, the greater the current generated.

Solar cells generate most of their electricity from direct sunlight. They can also generate electricity on cloudy days – and some systems can even generate very small amounts of electricity on bright moonlit nights.

Individual solar cells typically only generate tiny amounts of electrical energy. To make useful amounts of electricity, these cells are connected together to make a solar module, otherwise known as a solar panel or, to be more precise, a photovoltaic module.

Useful information solar panels:
http://www.scribd.com/doc/19967300/How-to-Build-Solar-Panel-Magnetic-Generator-Wind-Turbine-And-Solar-Water-Heater

Learn how to make a solar cell:
http://www.prlog.org/10270892-homemade-solar-cells-how-to-make-solar-cell.html

Useful information generate electricity:
http://ezinearticles.com/?Learn-How-to-Generate-Electricity-With-a-Magnetic-Generator&id=3380374