Teaching the principle of flywheel energy storage

How does a flywheel energy storage system work?

Flywheel Energy Storage Systems (FESS) rely on a mechanical working principle: An electric motor is used to spin a rotor of high inertia up to 20,000-50,000 rpm. Electrical energy is thus converted to kinetic energy for storage. For discharging, the motor acts as a generator, braking the rotor to produce electricity.

Are flywheel energy storage systems feasible?

Vaal University of Technology, Vanderbijlpark, Sou th Africa. Abstract - This study gives a critical review of flywheel energy storage systems and their feasibility in various applications. Flywheel energy storage systems have gained increased popularity as a method of environmentally friendly energy storage.

What is the difference between a flywheel and a battery storage system?

Flywheel Systems are more suited for applications that require rapid energy bursts, such as power grid stabilization, frequency regulation, and backup power for critical infrastructure. Battery Storage is typically a better choice for long-term energy storage, such as for renewable energy systems (solar or wind) or home energy storage.

How can flywheels be more competitive to batteries?

The use of new materials and compact designs will increase the specific energy and energy density to make flywheels more competitive to batteries. Other opportunities are new applications in energy harvest, hybrid energy systems, and flywheel’s secondary functionality apart from energy storage.

What is a magnetic bearing in a flywheel energy storage system?

In simple terms, a magnetic bearing uses permanent magnets to lift the flywheel and controlled electromagnets to keep the flywheel rotor steady. This stability needs a sophisticated control system with costly sensors. There are three types of magnetic bearings in a Flywheel Energy Storage System (FESS): passive, active, and superconducting.

How to connect flywheel energy storage system (fess) to an AC grid?

To connect the Flywheel Energy Storage System (FESS) to an AC grid, another bi-directional converter is necessary. This converter can be single-stage (AC-DC) or double-stage (AC-DC-AC). The power electronic interface has a high power capability, high switching frequency, and high efficiency.