what is silicon cells?
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what is silicon cells?
¿que es una célula solar?
This the method that uses semi conducting material to turn solar energy into current electricity.Solar panels have solar cells that turns photons into electrons which in turn create a flow of electricity.
What is mono crystalline silicon?
You have probably used direct conversion of solar energy to electricity through a solar cell that powers a pocket calculator or a solar ‘trickle’ charger to top up car batteries.
Both exploit the photovoltaic (PV) effect, first described in 1839 by Edmond Becquerel. He observed that the voltage of an early ‘wet cell’ battery increased when its silver plates were exposed to light.
In 1877 Cambridge physicists discovered that selenium crystals created an electrical current when exposed to light.
A New York electrician, Charles Edgar Fritts, devised the first working PV cells in 1883, using selenium plates covered in gold wires, but they converted less than 1% of the incident solar energy into electricity.
In the 1950s the Bell Telephone Company\'s laboratory in New Jersey, USA experimented on the effect of light on semiconductors, that had been invented as miniature analogues of the valves used in radios.
These first transistors were made of silicon that had been ‘doped’ with minute amounts of other elements, including boron or phosphorus. The impurities increase the electrical conductivity of poorly conductive silicon to that intermediate between non-conductors and metals -hence the name, semiconductor.
Solar PV cells based on doped crystalline silicon have a theoretical maximum efficiency of 28%, because only a narrow range of short wavelength radiation from the Sun has the appropriate energy to displace electrons.
In practice, they convert about 15% of the incoming solar energy in that wavelength range to electrical current. Crystalline silicon is durable but expensive to manufacture. Fine-grained, doped silicon formed into wafers is cheaper, but its efficiency is around 5 to 7%, and it eventually degrades.
Current research centres on low-cost semiconducting materials, one promising candidate being fine-grained titanium dioxide - the white pigment used in paints, and therefore cheaply available. Combined with dyes to increase the sensitivity of TiO2 to sunlight, it has a practical PV efficiency of 7 to 12%, and degrades very slowly.
Titanium dioxide occurs as a natural mineral, concentrated in some beach sands because of its high density. Titanium dioxide embedded in thin plastic films may prove to be a much cheaper alternative to silicon cells.