MIT Energy Initiative

High-performance flywheels for energy storage

Compact, durable motors that can operate at high speeds without overheating could increase the energy efficiency of a wide range of devices

Mohammad Imani-Nejad and David Trumper, from Designing high-speed motors for energy storage and more, Energy Futures Autumn 2013Credit: Stuart Darsch

We showed theoretically and experimentally that with the right controller you can make this system stable by controlling movement along just one axis. That makes it much less expensive and much less complicated – and very interesting for real-world applications.

Mohammad Imani-Nejad, PhD ’13

Devices from compressors to flywheels could be revolutionized if electric motors could run at higher speeds without getting hot and failing. MIT researchers have designed and built novel motors that promise to fulfill that dream. Central to their motors are spinning rotors of high-strength steel with no joints or bolts or magnets. Rather than resting those rotors on vulnerable bearings, the researchers levitate them by manipulating the steel’s natural magnetic “memory” to control the magnetic fields inside the device. Their contact-free designs are compact, efficient, and suited to low-cost manufacturing as well as high-speed operation. One motor is specially designed as a high-velocity flywheel for reliable, fast-response energy storage—a function that will become increasingly important as electric power systems become more reliant on intermittent energy sources such as solar and wind.

Research Team

Mohammad Imani-Nejad PhD '13 Laboratory for Manufacturing and Productivity

This research was supported in part by the MIT Energy Initiative Seed Fund