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Practical Uses
Makeup of a PVC
Creating Current
In The Future

    As a photon travels through space and comes into the atmosphere, only certain photons have enough energy to actually be used by the solar cell. Photons can do one of three things when they strike a solar cell. First, be absorbed; second, be reflected; and third, pass through the material altogether. Only the absorbed photons generate electricity.  As one would notice, since only a third of the photons are absorbed and photons must have a certain amount of energy in order to be used, solar appear to be inefficient. However since the sun is a constant resource and can be collected in large amounts, it turns out to be very reliable. As a photon passes through the glass and hits the n-layer of the solar cell, the photons excite the extra electron floating in the Phosphorus – Silicon crystal, and cause them to escape the crystal and move cause a potential difference between the n-layer and p-layer.  With the electron leaving the n-layer and escaping to the top terminal, there is an extra positive charge on the p-layer, while the n-layer has an extra positive charge. Since there is an electric field created, to be in equilibrium, the p-layer gives up an electron to fill up the hole caused by the photon hitting the electron. This, in turn, creates a negatively charged top terminal, and a positively charged bottom terminal, and thus creates a potential difference. The electron flows through wires from the top terminal to the bottom terminal, and causes the voltage to drop to zero. Voltage can be defined as a potential difference between two charges. Voltage is what causes electrons to flow between two places. A Voltage is created between the positive terminal and the negative terminal, and thus electrons flow to do work for us. Each solar cell may be set up in series. Since each cell operates as a battery, the total voltage will be the sum of each potential difference along the cells. With the voltage greater, the current will obviously run with more intensity. Below are some diagrams to help you better understand the process of Photovoltaic Current.