Flywheels are an ancient means of storing kinetic energy, the most widely used application being the potter's disk. Increasingly efficient frequency converters in conjunction with modern high speed motor-generator technology and advanced flywheel materials have opened new possibilities for flywheel in applications such as
Magnetic bearings levitate the flywheel without friction and are, therefore, the bearings of choice to optimize overall flywheel efficiency.
From the depicted steam engine to highly dynamic energy storage solutions, flywheels have come a long way. Today, flywheels operate in near vacuum conditions to reduce windage losses and are designed for dynamic and cyclical energy storage and retrieval. Further advantages are: absence of aggressive or toxic chemicals; long life cycle; and maintenance-free operation.
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