Solar Panel

• Solar cell (also called a photovoltaic cell) is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect. It is a form of photoelectric cell (in that its electrical characteristics—e.g. current, voltage, or resistance—vary when light is incident upon it) which, when exposed to light, can generate and support an electric current without being attached to any external voltage source, but do require an external load for power consumption.
• Photovoltaic comes from the Greek meaning "light", and from "volt", the unit of electro-motive force, the volt, which in turn comes from the last name of the Italian physicist Alessandro Volta, inventor of the battery.
• A solar panel, or module, is a series of interconnected silicon cells joined together to form a circuit. In greater numbers the amount of power produced by these interconnected cells can be increased and used as an electricity production system.Solar panels come in different sizes for different purposes. The current standard offering in the market is a 60-cell panel, with larger 72-cell panels being used for larger-scale installations. Smaller panels are also available and used in the off-grid market, where space is at a premium or for layouts where more flexibility is required. 
• At cell structure level, different kinds of panels exist, such as Monosilicon, Polysilicon or Thin-film. Monosilicon cells are manufactured from a single crystal. Their higher production costs leads to them being more expensive than other types. Monosilicon cells often have a higher efficiency rating than other technologies. However, as they are cut from cylindrical ingots, they do not completely cover a panel without substantial waste, lessening the efficiency of the overall panel. Poly-silicon cells are made from melting different silicon crystals together. These are less expensive to produce than monocrystalline, but less efficient. Recent times have seen much more investment in polysilicon technology and the best polysilicon panels now demonstrate a performance equal to or close to mono. This, coupled with the lower costs, has led polysilicon to emerge as the premier material for solar panels.