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Commercial and Residential Alternative Energy Systems |
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PV materials convert light energy into electrical energy. Crystalline silicon is the most widely used PV material. Silicon occurs naturally in many rock-forming minerals and in common beach sand. Silicon is the second most abundant element on the planet (after oxygen) making up 25% of the earth's crust. However the silicon used to make a PV cell must be very pure and perfectly crystalline. When light shines on crystalline silicon, electrons within the silicon are freed, generating an electric current. The design of and material used in the PV cell prevents the freed electrons from escaping. |
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A silicon ingot |
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Individual atoms on a silicon crystal enlarged over 1 billion times. |
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