I have often considered the workings of Tesla's custom Pierce Arrow A/C electric car. I believe that he was using vacuum tubes in the electrical generation system as a method of actually grounding out to the vacuum of space and was using an antenna on the car, paired with a magnetically wound low frequency oscillator, as the incoming source of positive current flow. I don't believe this is possible to achieve by any modern attempt using D/C, but I do believe that it could be used to produce A/C current as the electrons flow from the antenna material into the vacuum tubes, and back, creating an alternated current flow, without actually producing any positive or negative net flow of electrons between conductors. The push and pull of the current would of course be in conjunction with the frequency oscillations produced because of the Earth's natural magnetic field, leading me to believe that this effect can only be reproduced when grounding out to a vacuum. I believe that many people refer to it as zero point energy?