Flywheel Energy Storage Calculator
To calculate the energy stored in a flywheel, you can use the following formula for rotational kinetic energy:
Flywheel Energy Storage Formula:

Where:
- = Energy stored in the flywheel (Joules or Watt-seconds)
- = Moment of inertia of the flywheel (kg·m²)
- = Angular velocity of the flywheel (radians per second)
Moment of Inertia for a Flywheel:
The moment of inertia II
for a flywheel depends on its shape. For a simple solid disc, the moment of inertia is:
Where:
- = Mass of the flywheel (kg)
- = Radius of the flywheel (m)
For a flywheel with a more complex shape (like a hoop or ring), the formula would change accordingly.
Angular Velocity:
The angular velocity
can be calculated if you know the RPM (revolutions per minute) using the following relationship:
Where:
- = Angular velocity (radians per second)
- RPM = Revolutions per minute
Steps to Calculate Energy Stored in Flywheel:
- Calculate the moment of inertia of the flywheel.
- Convert the RPM (if provided) to angular velocity (radians per second).
- Use the energy formula to calculate the energy stored in the flywheel.