Thin-film technologies reduce the amount of active material in a cell. The active layer may be placed on a rigid substrate made from glass, plastic, or metal or the cell may be made with a flexible substrate like cloth. Thin-film solar cells tend to be cheaper than crystalline silicon cells and have a smaller ecological impact (determined from ). Their thin and flexible nature also.
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An uninterruptible power supply (UPS) or uninterruptible power source is an electrical apparatus that provides emergency power to a when the input power source or fails. A UPS differs from an auxiliary or or in that it will provide near-instantaneous protection from input power interruptions, by supplying energy stored in batteri.
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