The basic question seems to be "is it possible to make a generator based on electric charge and capacitance?" The answer to that question is yes. Electrostatic machines that are the "duals" of electromagnetic machines have been constructed and are currently being manufactured. There is currently ongoing research and development of such machines for use as motors and generators. The word "dual" indicates that, in electrostatic machines, electric fields, voltage and capacitance assume the roles of magnetic fields, current and inductance electromagnetic machines.
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