What are Flywheel Batteries?
Flywheels are a way of storing energy in the rotational momentum (kinetic energy) of large wheels sealed in a vacuum. They are used as a way of storing and releasing large amounts of electrical energy, and although their method of storage is non-chemical, arrays of flywheels are sometimes called batteries. Because the method of storage is mechanical rather than chemical, the amount of energy stored is only limited by the size of the flywheel, its ability to rotate quickly without tearing apart, and the motor/generator design. Flywheels have found use in specialized applications for which large, quick bursts of power are needed, such as in military rail guns or to provide the electricity to ignite fusion reactions. Flywheels are usually supported by magnetic bearings that don’t require any external power input. Hence, they are relatively inexpensive, reliable, and low-maintenance. Flywheels have been around for centuries, but it’s only recently that we’ve developed the high-quality vacu
