Firstly, this is NOT a duplicate question. There have been similar questions asked, but no one has adequately explained this particular aspect of electric generators. Yes, they act as an electron "pump", moving local electrons through their coils via magnetism. The issue here is supply. Being that ground is likely the return conduit, and being that air is supposedly an insulator, and being that a complete circuit is necessary for electron flow, how are electrons moving INTO the windings of a generator?
I would assume that air is not a perfect insulator, and that there is some ambient atmospheric electron flow, and that the electrons being pushed through the windings of a generator are pulled from the local atmosphere; but I haven't found this written down anywhere or alluded to.
If this is the case, then electric generators shouldn't work for very long without an atmosphere. If this is not the case, then, if not the from the local atmosphere, then from where are local free electrons being pulled?
A generator does not create electrons, and copper windings can only initially contain some finite amount of them. Electrons are pulled from and move through the atoms of various elements (some better than others, obviously), so how could electrons flow in a (perfect, uncontaminated, unmodified) vacuum with no medium (atoms) to flow through?