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.


WattsUp Power – flywheels have a long operational lifetime of more than 20 years. This results in a low over all cost per unit.

WattsUp Power flywheels have been designed and optimized to peak shape energy grids and can work as an individual unit or in parallel with other units. Each flywheel can in pulses adsorb 4.5 MJ and deliver 9MJ continually.

This significant cycle duty means WattsUp Power flywheels can outperform and outlast other storage technologies in high-cycle applications. And with partial depth-of-discharge cycles common in many applications, the cycle life increases substantially. Flywheels provide a great value in high-cycle applications, such as frequency regulation where rapid real-time adjustments correct generation and load imbalances to maintain grid frequency at 50/60 Hz, or smoothing and integrating the highly variable output of intermittent renewable resources like solar and wind.

Grid operators and utilities want to deliver the lowest lifetime cost of service for equipment in heavy workload utility system environments. WattsUp Power flywheels can handle heavy duty high-cycle workloads without the ongoing degradation that shortens the life of other technologies. The full 100% depth-of-discharge range is available for regular use. There is no need to limit depth-of-discharge to specific ranges to manage cycle life or to oversize the storage capacity. Unlike some other technologies, charge and discharge rates are symmetrical, meaning the units recharge as quickly as they discharge which enhances their operational effectiveness.

The flywheel is designed with the power-to-energy ratios needed for grid stabilizing and renewable power smoothing. With a lifespan of over 20 years in demanding high-cycle applications, the typical lifetime cost of a flywheel storage system is significantly less than competitive solutions.

Microgrid and isolated grids

Isolated grids such as islands, remote communities and remote industrial operations are typically cut off from larger grid infrastructure and therefore face unique challenges. They are often dependent on expensive liquid fossil-fueled generators for electricity supply. Renewable energy—such as wind and solar—introduces a path to escape from this expensive fossil fueled generation, but at a cost to grid stability. These grids are typically smaller and less diverse than major market grids, and stability cannot always be efficiently managed with generation alone—sometimes actions involve disconnecting loads.


WattsUp Power flywheel storage systems offer a grid stabilizing solution that provides frequency control and voltage support through active and reactive power injection and absorption. Flywheel storage increases the proportion of variable wind and solar that can be integrated, thus reducing fossil fuel consumption and associated cost as well as generation unit starts and stops and ramping related wear and tear.

Renewable Integration

A safe, reliable and energy-efficient modern grid should be capable of integrating renewable energy resources on a large scale without causing deterioration of performance. Renewable Portfolio Standards have been put in place in many regions to encourage greater market penetration of technologies such as wind and solar power. In other places due to fuel cost or availability, renewable energy is becoming a critical component of the energy supply base. Yet, the highly variable nature of these resources poses a challenge. Without new and more effective approaches for integrating variable generation resources, the deployment of renewable energy could be severely curtailed.


Power output from wind and solar resources is subject to sudden disruption from gusts of wind and passing clouds. Managing this variability has many power system operators searching for tools to stabilize frequency and voltage. WattsUp Power’s fast-responding, durable flywheels are the perfect solution for these high-cycle, high-power applications because they can instantly balance this short-term intermittency, to help restore local or grid-wide power quality. And the high-cycle design life means low costs over time.


Positive impact