Electric Energy Storage
(EES) is about reducing electricity consumption costs, improving network utilisation, energy supply reliability and improving power quality. There are various technologies for electric energy storage. Almost all technologies work with conversion of electrical energy into chemical, static, mechanical or thermal. Few technologies are based on electrical storage and discharge. These include capacitors or supercapacitors and superconducting magnetic coils
. In all others, the electrical energy is first converted into another form of energy.compressed air storage systems and flywheel energy storage systems, and thermal energy storage systems such as fuel cells
. Thecharacteristics of the various methods differ considerably in terms of the amount of energy, the start-up time, the discharge time and
the service life
. A decisive advantage of the storage of electrical energy is that the energy generated can be shifted and the time of energy retrieval is determined solely by the use. This means that electrical energy can be stored in converted form in a wide variety of energy storage systems in a decentralised manner, distributed across the supply network, for example in neighbourhood storage systems.