WattsUp Power’s – flywheel is essentially a mechanical battery that stores kinetic energy in a rotating mass. Advanced power electronics and a motor/generator convert that kinetic energy to electric energy, making it instantly available when needed. Our systems are modular and can be configured to meet the power capacity demands of a variety of applications, from 100 kW to multi-MW systems.


WattsUp Power’s flywheel technology is a patented composite rim, supported by a hub and shaft with an integrated motor and generator. Together, the rim, hub, shaft and motor/generator form the rotor assembly. Power electronics and the motor/generator efficiently convert electrical energy into mechanical energy when the flywheel is charging and back to electrical energy when discharging. When charging (or absorbing) energy, the flywheel’s motor acts like a load and draws power from the grid to accelerate the rotor to a higher speed. When discharging, the motor is switched into generator mode, and the inertial energy of the rotor drives the generator, creating electricity which is injected back into the grid. Always spinning in the same direction, the flywheel system can instantly shift back and forth between charging and discharging modes.


WattsUp Power’s high-performance rotor assembly spins up to 60,000 rpm. The rotor assembly is enclosed in a sealed vacuum chamber which provides a near frictionless environment and also eliminates exposure to oxygen and moisture which extends the life of the internal components. To reduce wear and further extend the life of the internal parts while minimizing friction, a magnetic lift system uses a non-contacting magnetic field to fully lift and support the rotor. WattsUp Power’s patented top and bottom bearing system ensures the spinning rotor maintains its axis of rotation with extremely low bearing loads. With the ability to perform more than 350.000 full depth charge and discharge cycles, WattsUp Power flywheels can outperform and outlast other storage technologies in high-cycle applications, and the robust design minimizes the need for flywheel system maintenance.