Abstract: A method and apparatus for the efficient conversion of energy into electrical energy of a preselected character utilizes programmable control to direct the storage and supply of energy in the form of an electrical signal of predetermined waveform with maximum flexibility as to the choice of waveform. An EMF ring, comprised of a plurality of charge storage elements arranged in a ring-like configuration, provides a medium for charge storage. A plurality of computer controlled switches allows the connection of selected charge storage elements to at least one output line, a voltage reference having been established, to thereby supply an electrical signal of preselected waveform thereto.