The energy transition represents a challenge not only for power production, but also for the grid and power distribution. The grid was built to distribute electricity from a few large power plants to many small consumers. With the switch to renewable energies, however, an increasing number of small producers are connecting to the grid, and the power supply is becoming more decentralised. In addition, unlike conventional power plants, wind turbines and solar panels do not bring forth a constant and predictable supply of electricity due to ever-changing weather conditions. This leads to strongly fluctuating electricity flows in the distribution network. In addition, the strain on the grid is amplified by the fact that the energy transition is accompanied by an increase in the number of power-consuming applications. Fossil-fuelled heating systems and cars, for instance, are being replaced by electrical systems. On the whole, it is becoming increasingly difficult to ensure balanced electricity production, consumption and storage at all times while keeping the mains voltage and the power load within the permissible range.