A solar cell or a photovolatic cell is a device comprising semiconductor (usually silicon) to function as diodes. When these diodes are shining, an electric current in the diode change direction. Each individual cell generates a relatively small voltage, because series connected to solar cells in solar panels. It can also be connected in parallel solar cells if you want to increase the current.
One can generally divide the solar panels into two groups, solar panels with crystalline solar cells and thin film solar cells. Crystalline cells are most prevalent today because they are more efficient than thin-film cells. They consist of silicon that has been doped with various substances to obtain the desired function. The crystalline cells can also be divided into two types, poly – crystalline or multi-crystalline and mono-crystalline cells.
Solar cells have historically been expensive and have mostly been used in places not reached by the grid, such as houses, satellites and lighthouses. The price of solar cells has, however, between 2000 and 2012 has fallen sharply as a result of technology development and expansion of production capacity in the world. As the price has fallen, the market has grown by an average of 40% since 2000 and by the end of 2011, there were approximately 64 GW solar capacity installed in the world, of which 98% consisted of systems connected to various national electricity grids.
In physical chemistry going on constant research on how to improve the efficiency of solar cells effect on production. The solar cell has many uses and is used for example also for charging smartphones, tablets and laptops.
In Sweden, the solar market cautious advancing. Total installed the 4.3 MW PV capacity in Sweden in 2011, which was an increase from 2010 when 2.7 MW installed. In total there were at the end of 2011, approximately 15.75 MW installed in Sweden, which is a production output which contributes about 15 GWh of electricity per year. The growing market was a result of the price in Sweden for both modules and complete turnkey systems more than halved in 2010 and 2011. In late 2011 the price of a single module around 19 SEK / W (exclusive of VAT) and a typical pre-installed systems for roofs for residential dwellings cost around 32 SEK / W. In 2012, installed 8.3 MW and 2013 were installed 19 MW in Sweden, giving a total installed peak power of 43.1 MW in Sweden at the end of 2013.
A solar panel that provides 100 watts (watts) costs about 1200 SEK which is 100 x 60 on the surface.