Daily tons of energy reaches the planet in an clean and free way. The sun’s rays, beyond bringing light and heat that are essential for life on Earth, can be used to generate electricity.
Through a technology called photovoltaic or, in other word,s light transformed into electricity.
To do this, it is used solar cell formed by two layers of semiconductor material, one positive and other negative. Upon reaching the cell, the photons from the light excite electrons, generating electricity. Greater is the intensity of the sun, greater is the flow of electricity.
The most commonly used material is silicon. As the second most abundant element on earth, there are no limits with respect to the raw material for solar cell production. The electricity generated by the cells is in direct current, which can be used immediately or stored in batteries. In systems connected to the network, the energy generated must go through a device called an inverter that will convert the direct current into alternating with the characteristics (frequency, harmonic content, waveform, etc.) necessary to meet the conditions imposed by the public grid. Thus, the energy which is not consumed may also be injected on the network.
The term ‘photovoltaic’ is a marriage of two words:
Photo = which has its root in the Greek language and means “light” and
Voltaic = which came from ‘volt’, which is the unit for measuring electrical potential.
Do not confused, thermal solar energy with photovoltaic solar energy!
In solar thermal systems, the sun energy is transformed into heat and is used to heat water in homes, hotels, clubs, etc… In this case, it is used solar COLLECTORS.
In solar photovoltaic systems, the energy is directly converted into electricity and, in this case, it is used Solar MODULES.
Read more at www.americadosol.org/en.