Flywheel energy storage is green and low-carbon

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

This mismatch between supply and demand necessitates effective energy storage solutions. While batteries have been the traditional method, flywheel energy storage systems (FESS) are emerging as an innovative and potentially superior alternative, particularly in applications like time-shifting solar power.

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.

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.

Flywheel systems are ideal for this form of energy time-shifting. Here's why: Solar power generation peaks in the middle of the day, but energy demand peaks in the late afternoon and early evening. Flywheels can quickly absorb excess solar energy during the day and rapidly discharge it as demand increases.

A flywheel is an onboard energy recovery and storage system that is durable, efficient, and environmentally friendly. It works by storing energy in a rotating mechanical device, the flywheel. The temperatures of the flywheel and its housing can be influenced by the friction-induced windage losses in the air-gap of a high-speed rotating flywheel.