New Affordable Energy Storage Technologies for Power Grids and Micro-Grids

AMT proposes a high density energy storage Electromechanical Battery (EMB) based on a unique flywheel system. The proposed module can both receive and deliver significant amounts of energy repeatedly. The system employs a novel ac homopolar motor design which guarantees a zero magnetic and dissipative loss during the storage cycle, thus eliminating what is the greatest loss component (1%) in comparable permanent magnet based competitors. This motor seamlessly solves the requirement of voltage coupling over a high range of speeds through a field winding which resides on the stator. The monolithic rotor makes it ideally suited to high speed and robustness; thus it offers a higher power density capability over competing energy storage solutions. The 3rd greatest loss component in similar energy storage systems, the active bearing (0.07%), is also reduced (approximately 1/3) by the use of a new trapped field magnet which acts as a magnetic bearing. During Phase I of the project, AMT proposes to complete the design of the EMB, compute the axial and transverse stiffness of the HTS magnetic bearings, and complete the design of the homopolar motor. During the Option Period, the Team will build and test the ac homopolar motor. During a potential Phase II, AMT, with the help of strategic partners, Huntsman Chemical, Inc. and Ricardo Inc., will build and test a 10 KW-hr energy storage module in conjunction with this proposal. Energy storage time and round trip efficiency are two key parameters sought in the testing.