What is a flywheel energy storage system?

First-generation flywheel energy-storage systems use a large steel flywheel rotating on mechanical bearings. Newer systems use carbon-fiber composite rotors that have a higher tensile strength than steel and can store much more energy for the same mass. To reduce friction, magnetic bearings are sometimes used instead of mechanical bearings.

Can a flywheel store energy?

A project team from Graz University of Technology (TU Graz) recently developed a prototype flywheel storage system that can store electrical energy and provide fast charging capabilities. Flywheels are considered one of the world’s oldest forms of energy storage, yet they are still relevant today.

Does a flywheel energy storage system affect the environment?

Flywheel energy storage system use is increasing, which has encouraged research in design improvement, performance optimization, and cost analysis. However, the system's environmental impacts for utility applications have not been widely studied.

What is a flywheel/kinetic energy storage system (fess)?

Thanks to the unique advantages such as long life cycles, high power density, minimal environmental impact, and high power quality such as fast response and voltage stability, the flywheel/kinetic energy storage system (FESS) is gaining attention recently.

How much energy does a flywheel produce?

The net energy ratios of steel and composite flywheels are 2.5–3.5 and 2.7–3.8. The GHG emissions of steel and composite flywheels are 75–121 and 49–95 kg CO 2 eq/MWh. Flywheel energy storage systems are feasible for short-duration applications, which are crucial for the reliability of an electrical grid with large renewable energy penetration.

How long does a fess flywheel last?

However, only a small percentage of the energy stored in them can be accessed, given the flywheel is synchronous (Ref. 2). FESS is used for short-time storage and typically offered with a charging/discharging duration between 20 seconds and 20 minutes. However, one 4-hour duration system is available on the market.