The average car already contains about a mile of copper wire connecting the sensors and electrical components that help it function. In electric cars we need three or four times the amount of copper, with about half of that going into the motors and the rest into the wiring harness and battery. A battery-powered bus will require nearly half a tonne of copper in motors and circuitry and large slabs—busbars as they’re called—capable of carrying even more current than conventional wires. High-speed trains will need even more.[22]
