Voltage Drop - Using Higher Voltages

Using Higher Voltages

Over long distances, larger conductors become expensive, and it is preferable to redesign the circuit to operate at a higher voltage. Doubling the voltage halves the current required to deliver the same amount of power, halving the voltage drop, and an additional doubling in efficiency is realized because that drop is a smaller fraction of the total voltage.

This is the motivation for commercial high voltage electrical power distribution, and for the use of the +12V power supply rail for high-power loads in modern personal computers.