A flywheel is an inertial energy storage device. It absorbs mechanical energy and serves as a reservoir, storing energy during the period when the supply of energy is more than the requirement and releases it during the period when required and releases it during the period when the requirement of energy is more than the supply.
A flywheel energy storage can have energy fed in the rotational mass of a flywheel, store it as kinetic energy, and release out upon demand. They work by spinning up a heavy disk or rotor to high speeds and then tapping that rotational energy to discharge high power bursts of electricity.
It is difficult to use flywheels to store energy for longer duration. The main cause of this problem is ‘coasting losses‘. These are the electromagnetic and mechanical forces that slow down a heavy spinning object.
Generally, flywheels are designed for a low cost per watt, short duration, and high-density.
The amount of energy stored in the flywheel is proportional to the material strength. Steel, glass fiber, Kevlar fiber and carbon fiber are the materials used as flywheel materials. Steel is the most cost-effective flywheel material. Steel has high strength per cost as compared to other materials.
Components of Flywheel
- Power Electronics
Flywheels Advantages Over Batteries
- No degradation in power
- No daily cycling limitations
- No degradation in energy
- Full power over full SOC range
- Zero variable O&M
- Highly accurate SOC measurement
- Utility customer comfort with rotating machinery
- Easily recyclable
- High residual value at the end of life.
Advantages of Flywheel
- Flywheel system has longer lives than batteries.
- Machine using flywheel can live for more than 20 years.
Disadvantages of Flywheel
- Flywheel includes the danger of explosive shattering of the massive wheel due to overload. Thus having the safety concern.