The application of new storage concepts, such as, for example, the seasonal heat storage or the use of superconductive magnetic energy storage, can increase the realizable saving of primary energy in an energy supply system by combined heat and power (KWK) noticeably, if the Loading and unloading of the accumulators is controlled optimally. Beside the technical characteristic values of the combined heat and power plants, especially the structure of the temporally fluctuating demand on heat and electric energy has an influence on the saving potential of primary energy. If the demand on heat and electric energy is known from a temporal point of view, so simple model calculations already allow a determination of the realizable saving potential of the primary energy by combined heat and power and accumulator use. More exact results can be obtained through the application of dynamic optimization models.