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Types Of Photovoltaics

Photovoltaics is the direct conversion of sunlight into electric current. This is done through photovoltaic cells, also called solar cells. A photovoltaic cell is made from silicon, which is doped with other elements to affect the behavior. The quality of electricity produced from solar cell depends on the intensity of the sunlight falling on the cell's surface. There are three main types of photovoltaic cells used for both residential and commercial applications.

  1. Monocrystalline Photovoltaic Solar Panel

    • A monocrystalline solar module is made from a large crystal of silicon. It is the most efficient and expensive solar cell available, as of June 2011. Because of its high efficiency, the cell is used in solar farms, where electricity is produced on a large scale. Unlike a polycrystalline solar module, which is made by combining multiple silicon crystals, it is made from a single silicon crystal and, therefore, is the most complex and costly. The expected life of monocrystalline cells is about 25 years.

    Polycrystalline Photovoltaic Solar Panel

    • A polycrystalline solar module is made from multiple crystals of silicon by joining them through wires in a single packing. These are the most commonly used solar panels because of their lower cost, but they are less efficient than monocrystalline solar cells. The maintenance cost of polycrystalline cells is lower than the maintenance cost of monocrystalline cells, because if a single cell of polycrystalline solar panel is damaged, it can be replaced easily without replacing the panel, whereas if a monocrystalline solar cell is damaged, it cannot be replaced.

    String Ribbon Silicon Panels

    • String ribbon silicon panels are similar to the polycrystalline silicon panels and are of almost the same efficiency in electricity production. The only difference is that the photovoltaic cells in a string ribbon panel are made of strips of silicon attached to metal bars. The production cost of string ribbon silicon is lower than for a polycrystalline silicon panel.

    Amorphous Silicon or Thin Film Solar Panel

    • These are the least electricity producing solar panels, having an electricity conversion rate of 5 to 6 percent. This is because they are not produced from crystalline silicon, but from a piece of semi-conductive metal with a thin silicon film over the top. They are less costly, but not cost effective. These cells are flexible in shape and are not affected by shading.

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