[mikeash]

Stupid question: if UHV lines need roughly the space of an interstate highway, could the right of way be acquired by building them along interstate highways? There's lots of grassy medians in which to put towers, and the lines themselves are comfortably off the ground.

Dumb idea, or dumbest idea ever?

[foxylad]

Not a bad idea, although you'd want extra protection for the pylons so a truck running into one didn't take out the grid.

[pkulak]

Millions of DC volts next to a steady stream of cars and trucks?

[mikeash]

Yes, nothing can possibligh go wrong.