Safe, sustainable, proven


Amber Kinetics: Longer Duration, Lower Cost Flywheels


Mechanical Battery

A flywheel, also known as a mechanical battery, converts and stores electrical energy in a rotating mass. Mechanical batteries have several advantages: unlimited daily cycling capability, high round-trip efficiency, zero capacity degradation, no chemical reactions; however, mechanical batteries have historically faced two unique challenges – high cost and short durations.


Amber Kinetics’ co-founder Dr. Seth Sanders first solved the fundamental cost challenge by re-developing the flywheel rotor’s metallurgical properties, evolving and refining the low-carbon steel alloy’s chemistry and processing steps to achieve a nearly ideal crystalline structure in the final part. The resulting combination is a low-cost, high-strength rotor, which is capable of achieving higher performance than traditional steels.


Extending the mechanical battery discharge duration from minutes to hours was the second challenge, solved by innovating in the electromagnetics and power conversion steps involved in accelerating and decelerating the mechanical battery, enabling nearly zero-loss operation of the storage system in standby mode.

Whereas previous generations of mechanical batteries were limited to between 1-15 minutes of duration, Amber Kinetics’ breakthrough in electromagnetics enables the company to offer customers 4 hours of discharge duration, and can be extended even longer if needed.