The energy supply underlies a fundamental change. With the trend of decentralization, more and more energy (electricity, heat, mobility) will be generated in buildings in the future. This trend is associated with an increased sales of various, in particular small, energy devices, e.g. combined heat and power plants, photovoltaic systems, heat pumps, battery storages, fuel cells or electric vehicles. Today’s networking technologies for decentralized energy systems are Virtual Power Plants, which are reaching economic limits if they should integrate small energy devices. On the other hand, DieEnergiekoppler GmbH connect small energy devices in particular economically and use the flexibility of energy devices for the marketing and creation of energy communities. This transforms residential and commercial buildings with energy devices into energy cells, which supply themself with energy.