> The more amps, the thicker the wires need to be (volts are irrelvant). Nitpick: the wire as a whole includes insulation, which technically does need to be th

> The more amps, the thicker the wires need to be (volts are irrelvant). Nitpick: the wire as a whole includes insulation, which technically does need to be thicker at high voltage (though at 40-60V, and maybe even at 40-60kV, it's probably dominated by tolerances for erosion and abrasion and such). High voltage power lines use air, which is actually a fairly good insulator per se, but has the problem that wires tend to pass through it on their way to a short circuit if not well-restrained.