Compare two transmission lines: one at twice the voltage of the second. Which of the two lines is most advantageous to a utility company? How much is the advantage?

Answer 1

Advantage has multi facets.

With twice the voltage, the joule heating will be 1/4 less if the same amount of power is transmitted (Power=V^2/load), or, four times more power can be transmitted with the same loss. Or, the area of the transmission lines can be 1/4 the original size (smaller, lighter wires) for the same power transmitted and losses.

Answer 2

Where can I find more information about the equation (Power=V^2/load)?

Answer 3

This is Ohm's Law. Search Google on that.