That’s a great idea.
To tweak that a little - instead of an empty, maybe have short tube surrounding the conductor (only as long as the wave you want), but very close to the surface of the conductor. Play with the alpha value to get it almost transparent, and emit/color/whatever of the cylinder, and animate it along the conductor. The material could also use the ramp shaders for a cool effect, I think. Also, you could have a comet tail like effect, probably, too.
Depending on your camera angle, it could work.
(Caveat - I’m new at this, so it might be a sucky idea.)
Edit - oops - I just realized I assumed a wire-type conductor. If its something else, my idea probably wouldn’t work so good…
edit 2 - another idea… maybe just animate a lamp traveling down the conductor? Could play with the color of the light, even.