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.

Could flywheels be the future of energy storage?

Flywheels, one of the earliest forms of energy storage, could play a significant role in the transformation of the electrical power system into one that is fully sustainable yet low cost.

What is a flywheel energy storage system?

Fig. 1 has been produced to illustrate the flywheel energy storage system, including its sub-components and the related technologies. A FESS consists of several key components: (1) A rotor/flywheel for storing the kinetic energy. (2) A bearing system to support the ro-tor/flywheel.

How much energy does a flywheel store?

Indeed, the development of high strength, low-density carbon fiber composites (CFCs) in the 1970s generated renewed interest in flywheel energy storage. Based on design strengths typically used in commercial flywheels, σmax /ρ is around 600 kNm/kg for CFC, whereas for wrought flywheel steels, it is around 75 kNm/kg.

Are flywheel-based hybrid energy storage systems based on compressed air energy storage?

While many papers compare different ESS technologies, only a few research [152,153] studies design and control flywheel-based hybrid energy storage systems. Recently, Zhang et al. present a hybrid energy storage system based on compressed air energy storage and FESS.

Why are high-strength steel flywheels a good choice?

High-strength steel flywheels have a high energy density (volume-based energy) due to their high mass density. Furthermore, they are superior to composite ones regarding thermal conductivity and design data availability, such as SN curves and fracture toughness.