This is not exactly in the context of this thread, but I stumbled across a 25 year old paper by one of our favorite visionaries - Robert Forward (well named) and it could be updated, based on new research:
http://prola.aps.org/abstract/PRB/v30/i4/p1700_1 "A pair of conducting plates at close distances experience an attractive Casimir force that is due to the electromagnetic zero-point fluctuations of the vacuum. A "vacuum-fluctuation battery" can be constructed by using the Casimir force to do work on a stack of charged conducting plates. By applying a charge of the same polarity to each conducting plate, a repulsive electrostatic force will be produced that opposes the Casimir force. If the applied electrostatic force is adjusted to be always slightly less than the Casimir force, the plates will move toward each other and the Casimir force will add energy to the electric field between the plates. The battery can be recharged by making the electrical forces slightly stronger than the Casimir force to reexpand the foliated conductor." Ostensibly this kind of cap-batt would work at very high frequency - terahertz and up . but course, for there to be a net gain, the recharging cycle (if it is not deducted from the "added energy" itself) must be lower in expenditure than the extraction cycle. yet this experiment is something that probably could be accomplished today with MEMS techniques, at least in silicon valley and elsewhere. It would be almost meaningless to opine how it would turn out without actually doing it. Jones
