“…It is estimated that investments in SG technologies had reached €3.15 billion in Europe by the end of 2014, underlining their growing significance. 113 The impact of SG projects and their suitability for large-scale applications has been investigated, such as by Rodriguez-Calvo et al 23 Within SGs, the devices of DEPs can be used to provide flexibility by • Transferring energy between the energy sectors within the SES • Support of RES integration if controlled flexibly • Support of wind integration even if not controlled flexibly 24,[36][37][38] • Causation of more frequent and higher peaks • Least-cost operation results in less RES friendliness [38][39][40] • Load shifting possibilities if operated flexibly • Reduction of required reserve capacity 24,37 • Dependency on storage type and size, control strategy and building physics 24,38,41 • Voltage regulation • Increased efficiencies in virtual power plants 5,37,38,40,42 • Suitability limited to low-temperature heat markets in DH 43 • High efficiency • Increased flexibility in DH 36,37,40,41,44,45 • Efficiency losses caused by flexible HP operation 41,46 • Integration of RES 36,47,48 • Not suited for wind power integration 40,49 • Increase in supply security [50][51][52] • Risk averse operation of CHPs causes less profit through flexibility programs 53 • Voltage and frequency regulation • Reduction of system operation cost •...…”