Patent ID: 8664815

Claim:
A flywheel based energy storage apparatus, comprising: a housing; a hub-less, ring-shaped flywheel mounted within the housing and rotatable about a horizontal axis, wherein the flywheel comprises a plurality of magnets aligned to form a rotor; a flywheel support system; and a plurality of coils, the plurality of coils and the rotor being aligned to form a motor/generator, wherein the flywheel support system comprises: a primary flywheel support for supporting the flywheel when the flywheel is spinning at and above a predetermined rotational speed; and a secondary flywheel support for supporting the flywheel when the flywheel is spinning at less than the predetermined rotational speed and, wherein the primary flywheel support comprises: a plurality of brackets attached to the plurality of outer frame members; a plurality of side air bearings mounted on the brackets and supporting the radially extending side surfaces of the flywheel; a plurality of radial air bearings mounted on the brackets and supporting the outer axially extending annular surface of the flywheel; a compressed air supply; and a plurality of air control valves for selectively supplying air from the compressed air supply to the plurality of air bearings.