Solar Cells

Solar Cells are a large area of semiconductor diodes. The Photovoltaic effect the energy of light converted into the elcetrical energy. At the P-N junction an electric field is built up which leads to the seperation of the charge carriers. At incidence of photon stream onto semiconductor material the electrons are released, if the energy of the photons is sufficient. Contact to a solar cell is realised because of the metal contacts.
http://www.pvresources.com/en/solarcells.php
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Photovoltaic Modules

A photovoltaic Module is the basic element for each array. It contains many jointly connected solar cells. According to the solar cell technology we figured out that the mono cystalline, polycrystalline and amorphous solar modules. Solar panels make use of renewable energy from the sun, and are a clean and environmentally sound means of collecting solar energy.
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Discover the process of making a solar panel

Making a solar panel is a very hard process, this reason is why the major solar advances did not come into play until later most quater of the last century, when advances in semiconductor and photovoltaic design allowed increasingly efficiend and affordable solar cells to be developed.
Crystalline Silicon Solar Panels
The creation of solar panels typically involves cutting crystalline silicon into tiny disks less than a centimeter thick. Then the little wafer like disks are very carefully polished and treated to repair and gloss any damage from the sclicing process. After they are polished, metal conductors are spread across each disk. The conductors are aligned in a thin, gril-like matrix on the top of the solar panel, and are spread in a flat sheet on the side facing the earth. Solar panels generate electricity using the same principles of electronics as chemical batteries or standard electrical outlets. With solar panels it's all about the free flow of electrons through a circuit.

How do they work?

The basic element of solar panels is the same element that helped create the Computer revolution, which is pure silicone. When silicon is stripped of all impurities, it makes a ideal neutral platform for the transmission of electrons. Silicon also has some atomic-level properties which make it even more attractive for the creation of solar panels.
Silicon atoms have room for eight electrons in their outer bands, but only carry four in their natural state. This means there is room for four more electrons. If one silicon atom contacts another silicon atom, each receives the other atom's four electrons. This creates a strong bond, but there is no positive or negative charge because the eight electrons satisfy the atoms' needs. Silicon atoms can combine for years to result in a large piece of pure silicon. This material is used to form the plates of solar panels. In order for electricity to flow, a positive charge must also be created. This is achieved in solar panels by combining silicon with an element such a boron, which only has three electrons to offer. A silicon and boron plate still has one spot left for another electron. This means the plate has a positive charge. The two plates are sandwiched together in solar panels, with conductive wires running between them. With the two plates in place, it's now time to bring in the 'solar' aspect of solar panels. Natural sunlight sends out many different particles of energy, but the one we're most interested in is called a photon. A photon essentially acts like a moving hammer. When the negative plates of solar cells are pointed at a proper angle to the sun, photons bombard the silicon and phosphorus atoms.

Who Created Solar Power Cells?
Charles Fritts, an American Inventor, and the creator of the first working power cell.
Antoine Cesar Becquerel, a french scientist who was the first person to notice photovoltaic in the year 1839.
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Charles Fritts
Antoine Cesar Becquerel
Antoine Cesar Becquerel


History of the Solar Cell.

The first Silicon based solar cell was developed by Russell Ohl, he worked at the the Bell Laboratory in the year of 1941.The development of the solar cell stems from the work of the French experimental physicist Antoine-César Becquerel back in the 19Th century. In 1839, Becquerel discovered the photovoltaic effect while experimenting with an electric cell containing two metal electrodes. Then the nineteen year old found that certain metals and solutions would produce small amounts of electric current when exposed to light.In 1877, Charles Fritts made the first solar cells by using junctions formed by coating the semiconductor selenium with an ultra-thin, nearly transparent layer of gold. Fritts's devices were very improvident, transforming less than 1 percent of the absorbed light into electrical energy, but that was a start.
Substantial improvements in solar cell efficiency had to wait for a better understanding of the physical principles involved in their design, provided by Einstein in 1905 and Schottky in 1930. By 1927 another semiconductor-junction solar cell, in this case made of copper and the semiconductor copper oxide, had been demonstrated. By the 1930s both the selenium cell and the copper oxide cell were being employed in light-sensitive devices, such as photometers, for use in photography. These early solar cells, however, still had energy conversion efficiencies of less than 1 percent. (So they made fine light sensors, but very bad energy converters) Solar cell efficiency finally saw substantial progress with the development of the first silicon cell by Russell Ohl in 1941. In 1954, three other American researchers, G.L. Pearson, Daryl Chapin, and Calvin Fuller, demonstrated a further-refined silicon solar cell capable of a 6% energy conversion efficiency in direct sunlight. By the late 1980s silicon cells, as well as those made of gallium arsenide, with efficiencies of more than 20% had been fabricated. In 1989 a concentrator solar cell, a type of device in which sunlight is concentrated onto the cell surface by means of lenses, achieved an efficiency of 37% thanks to the increased intensity of the collected energy. Modern solar cells are basically just P-N junction photo-diodes with a very large light-sensitive area. So let's move along to get a bit of background on the semiconductor physics involved here.

Benefits to the environment

The Solar Cell benefits to the environment by many ways! First of all, it helps by not using as much electricity, so many people are not dying by having to burn fossil fuel for electricity. It is a completely natural way to create power, and energy. It only needs sunlight to make it work, and you can use it to help save a lot of money!
The Solar Cell saves electricity because you do not have to use as much! This device attracts enough electrons to generate electricity, to power an entire family sized home.

Deficits
There are a few downers to the Solar Panel Projects, they are expensive. I think in the long run it is worth it, because you end up saving more money from your electricity bill!
The other downers are the could break if something were to land on it, and they are even more expensive to fix.


Examples-

Some items that use Solar Cells are,
Houses, they put them on the top of the roof, and that powers the percentage of the house
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Microwaves,
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Computer,
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Televisions,
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and Flashlights.
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If you want to get something other than listed,
as a solor panel powered you can place an
order, and create one!


References-

http://www.pvresources.com/en/solarcells.php
http://www.solarpanelinfo.com/solar-panels/how-are-solar-panels-made.php
http://www.wisegeek.com/how-do-solar-panels-work.htm
http://www.thegeminigeek.com/who-invented-solar-panels/
http://www.solarpanelinfo.com/