A gyroscopic roll stabilizer comprises a gimbal having a support frame and enclosure configured to maintain a below-ambient pressure, a flywheel assembly including a flywheel and flywheel shaft, one or more bearings for rotatably mounting the flywheel inside the enclosure, a motor for rotating the flywheel, and bearing cooling system for cooling the bearings supporting the flywheel. For smaller units, the bearing cooling system is effective to enable a flywheel with a moment of inertia less than 40,000 lb in.sup.2 to be accelerated at a rate of 5 rpm/s or greater. For larger units, the bearing cooling system is effective to enable a flywheel with a moment of inertia greater than 40,000 lb in.sup.2 to be accelerated at a rate of 2.5 rpm/s or greater.

An electric machine including a first energy consuming unit and a second energy consuming unit, the first energy consuming unit requiring a higher power energy source and the second energy consuming unit requiring a lower power energy source, wherein the machine further includes a first energy storage device and a second energy storage device, the first energy storage device having a higher power with respect to the second energy storage device, wherein the first energy storage device is configured to power the first energy consuming unit, wherein the second energy storage device is configured to power the second energy consuming unit, and wherein the first energy storage device is connectable to a charger for charging, the first energy storage device requiring a lower charging time for reaching its maximum state of charge than the second energy storage device, and wherein the first energy storage device is configured to directly provide power to the first energy consuming unit.

A system may include a first node having a first mechanical energy storage unit (MESU) located in a first geographical location, the first node being coupled for communication with an energy as a service (EaaS) platform. A system may include a second node having a second MESU located in a second geographical location that is distinct from the first geographical location, the second node being coupled for communication with the EaaS platform, wherein the first MESU of the first node and the second MESU of the second node are each configured to send a power banking status to the EaaS platform and to extract or bank power based on signals received from the EaaS platform.

A hub motor is disclosed, the hub motor is mounted on an axle assembly, the an axle assembly includes an axle rod and an axle sleeve, and an independent cassette flywheel is provided at one end of the axle sleeve where an end cover is located, a limiting sleeve is disposed outside of the cassette flywheel to prevent the cassette flywheel from detaching from the axle sleeve, and an anti-rotation piece for preventing rotation of the axle sleeve is provided at another end of the axle sleeve where a wheel hub is located.

A hub motor is disclosed, the hub motor is mounted on an axle assembly, the an axle assembly includes an axle rod and an axle sleeve, and an independent cassette flywheel is provided at one end of the axle sleeve where an end cover is located, a limiting sleeve is disposed outside of the cassette flywheel to prevent the cassette flywheel from detaching from the axle sleeve, and an anti-rotation piece for preventing rotation of the axle sleeve is provided at another end of the axle sleeve where a wheel hub is located.

A gyroscopic roll stabilizer includes an enclosure, a flywheel assembly, and a motor. The enclosure is mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure. The flywheel assembly is rotatably mounted inside the enclosure for rotation about a flywheel axis. The flywheel assembly includes a flywheel and flywheel shaft. The flywheel shaft has a first end and an opposite second end; a first cavity formed in the first end and facing away from the second end; and a second cavity formed in the second end and facing away from the first end. The flywheel shaft has a longitudinal passage connecting the first cavity and the second cavity. This longitudinal passage may be used for inspection of one of the cavities and/or an associated seal, from the direction of the other cavity. Related methods are also disclosed.

A gyroscopic roll stabilizer includes an enclosure, a flywheel assembly, and a motor. The enclosure is mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure. The flywheel assembly is rotatably mounted inside the enclosure for rotation about a flywheel axis. The flywheel assembly includes a flywheel and flywheel shaft. The flywheel shaft has a first end and an opposite second end; a first cavity formed in the first end and facing away from the second end; and a second cavity formed in the second end and facing away from the first end. The flywheel shaft has a longitudinal passage connecting the first cavity and the second cavity. This longitudinal passage may be used for inspection of one of the cavities and/or an associated seal, from the direction of the other cavity. Related methods are also disclosed.

This disclosure describes novel hybrid energy storage systems for providing short-term and long-term storage and delivery of electricity generated by any energy source including renewable energy sources such as solar energy and wind energy. The hybrid energy storage systems described herein have a higher overall real-world efficiency than energy storage systems currently available.

A gyroscopic roll stabilizer for a boat includes an enclosure mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure, and a flywheel assembly including a flywheel and flywheel shaft, with the flywheel assembly rotatably mounted inside the enclosure for rotation about a flywheel axis. The gyroscopic roll stabilizer also includes a motor operative to rotate the flywheel assembly and disposed inside the enclosure. A motor cooling circuit is configured to transfer heat away from the motor. The motor cooling circuit has a closed fluid pathway for recirculating cooling fluid therein. The fluid pathway includes a fluid channel jointly defined by the motor and the enclosure and having the cooling fluid therein. The gyroscopic roll stabilizer is configured to transfer heat away from the motor to the cooling fluid. Related methods are also disclosed.

A gyroscopic roll stabilizer for a boat includes an enclosure mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure, and a flywheel assembly including a flywheel and flywheel shaft, with the flywheel assembly rotatably mounted inside the enclosure for rotation about a flywheel axis. The gyroscopic roll stabilizer also includes a motor operative to rotate the flywheel assembly and disposed inside the enclosure. A motor cooling circuit is configured to transfer heat away from the motor. The motor cooling circuit has a closed fluid pathway for recirculating cooling fluid therein. The fluid pathway includes a fluid channel jointly defined by the motor and the enclosure and having the cooling fluid therein. The gyroscopic roll stabilizer is configured to transfer heat away from the motor to the cooling fluid. Related methods are also disclosed.