Due to the highly interdisciplinary nature of FESSs, we survey different design approaches, choices of subsystems, and the effects on performance, cost, and applications. This review focuses on the state of the art of FESS technologies, especially those commissioned or prototyped. We also. . Compared with other energy storage systems, FESSs offer numerous advantages, including a long lifespan, exceptional efficiency, high power density, and minimal environmental impact. This article comprehensively reviews the key components of FESSs, including flywheel rotors, motor types, bearing. . The Flywheel Energy Storage Equipment Market was valued at USD 1. 5 billion in 2024 and is projected to reach USD 4. This growth trajectory is underpinned by the increasing demand for efficient energy storage solutions, particularly in the context of. . Abstract - This study gives a critical review of flywheel energy storage systems and their feasibility in various applications. Fly wheels store energy in mechanical rotational. . ad application prospects in the field of rail transit. This paper introduces the basic structure and principle of flywheel energy storage, analyzes the energy storage density of the rotor in both metal and composite materials, and points out that composite materials such as T1 00 fiber/resin have. . ch leads to economic growth and productivity. In recent national development plans and policies, numerous nation have prioritized sustainable energy storage. To promote sustainable energy use, energy storage systems are being depl indispensable in the energy and power sector. The flywheel energy. .