Our flywheel energy storage calculator allows you to calculate the capacity of an interesting type of battery!
Consider a flywheel with a certain mass and radius, spinning at a specified angular velocity. By inputting these values into the calculator, you receive the total kinetic energy stored. For instance, if a flywheel with a mass of 20 kg and a radius of 0.5 m spins at 3000 RPM, the calculator will provide the energy stored in Joules.
Flywheel energy storage systems typically have efficiencies of around 90%, meaning that 10% of the energy is lost during storage and discharge. This efficiency loss must be taken into account when determining the required energy capacity of the system.
They do so by accelerating a rotor to a high speed and maintaining the energy in the system as rotational energy. When energy is needed from the system, the flywheel's rotational speed is reduced to release the stored energy, typically to perform work or balance energy demand.
The flywheel energy storage operating principle has many parallels with conventional battery-based energy storage. The flywheel goes through three stages during an operational cycle, like all types of energy storage systems: The flywheel speeds up: this is the charging process.
The next factor to consider is the discharge time, which specifies how long the energy needs to be discharged. This value is important in determining the size of the flywheel and the amount of energy storage that is needed. For example, a 1 MW system designed to discharge for 1 hour would require a flywheel with a stored energy capacity of 1 MWh.