A method and circuit arrangement for covering peak energy demand in an electrical AC or three-phase current network having a plurality of consumers of which at least some of the consumers are equipped with a stand-by power supply network having accumulators and at least one rectifier fed from the electrical network. The method includes feeding a fraction of energy from the accumulators of each individual stand-by power supply network into the electrical network via inverters for a short term peak demand of the electrical network. The fraction of energy is fed from the accumulators as long as peak demand is present and sufficient energy for the stand-by power supply is still available in the accumulators.