Using your definition, the generator on my bicycle and the wires to a light on the front of it would be covered by the NEC. My bicycle is not grounded nor does it have listed CL2 cabling. If a generator, battery, or similar is not really portable (i.e. it weighs over 200 lbs and doesn't have wheels or it is hard wired into building wiring) then I could believe your interpretation of premesis wiring.
