This calculator lets you see the amount of voltage is lost due to inefficiencies in transmission over electrical copper wires. Note that supplied voltage, supplied current, gauge of wire and length contribute to voltage loss. After you have determined the type of pump (or other device) needing to be powered and the length of the wire between your solar panels and the device, use this calculator to determine the correct gauge of wire you will need and the amount of power your panels will be able to supply.
DC Voltage Loss
Provide the following information about your input source and wire to compute its output voltage and loss.