Stadtwerke München (SWM, Munich, Germany) uses a flywheel storage power system to stabilize the power grid, as well as control energy and to compensate for deviations from renewable energy sources. .
A flywheel-storage power system uses a for , (see ) and can be a comparatively small storage facility with a peak power of up to 20 MW. It typically is used to stabilize to. .
China has the largest grid-scale flywheel energy storage plant in the world with 30 MW capacity. The system was connected to the grid in 2024 and it was the first such system in China. .
Power grid frequency controlIn , operates in a flywheel storage power plant with 200 flywheels of. .
It is now (since 2013) possible to build a flywheel storage system that loses just 5 percent of the energy stored in it, per day (i.e. the self-discharge rate).
[pdf] Flywheels store rotational kinetic energy in the form of a spinning cylinder or disc, then use this stored kinetic energy to regenerate electricity at a later time. The amount of energy stored in a flywheel depends on the dimensions of the flywheel, its mass, and the rate at which it spins.
[pdf] Flywheel energy storage (FES) works by accelerating a rotor () to a very high speed and maintaining the energy in the system as . When energy is extracted from the system, the flywheel's rotational speed is reduced as a consequence of the principle of ; adding energy to the system correspondingly results in an increase in the speed of th.
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