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Question:

Solar Panel load resistors?

When you add a load resistor to a PV panel (Solar panel) of 00 ohms what happens to the voltage produced from the cellAlso, as the resistance increases, how does this affect the output voltage

Answer:

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Photovoltaic cells have a load curve that gives the power conversion based on the current drawn. This makes it harder to calculate. For instance, at infinite resistance, the solar cell will have a peak voltage that produces no power (P=I*V=V^2/r). At short circuit, the voltage collapses to essentially nothing and so the power is almost nothing. There is an optimal load (sweet spot) where the resistance applied will draw the most power out of the cell while not overloading it. This measure is either given by the manufacturer or found experimentally. Upon taking a lit panel that has no load and applying a 00 ohm resistance, the voltage will drop. By how much is entirely dependent on the array layout and specific cell characteristics. As the resistance drops from the optimal load point, the voltage collapses fairly sharply. As the resistance increases from the optimal load point, the voltage will rise more at first and then level off to the peak or no-load voltage.
Look at the graph data that looks like a rotated L. That is what voltage as a function of current characteristically behaves. The highest voltage value is called open circuit voltage (Voc). The current at lowest voltage value is called short circuit current (Isc). If you notice, a second curve is plotted that looks like a hill. That curve is power output as a function of voltage. At the peak of said hill, you get the most utility of your PV module, as you output the maximum power possible, and that is the nameplate value for the PV module's power rating.
Solar Panel Load

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