Advanced Flywheel Energy Storage for Pulsed Power Applications
Navy STTR FY2004

Sol No.: Navy STTR FY2004
Topic No.: N04-T013
Topic Title: Advanced Flywheel Energy Storage for Pulsed Power Applications
Proposal No.: N045-013-0384
Firm: Calnetix
12880 Moore Street
Cerritos, California 90703
Contact: Patrick McMullen
Phone: (562) 293-1685
Web Site:
Abstract: Existing battery based energy storage systems are not suited for short duration, high cycle life, deep discharge, and small required size applications. Ultra/super capacitors (UC) are limited by some of the same issues as batteries, i.e. cycle life limitations, disposal, and continue to remain at a much higher cost than batteries. Flywheels can cost effectively fill the short duration, high cycle life applications that batteries and UC's cannot, specifically as products that are cost competitive with existing battery based systems for specific applications where flywheels out perform and offer benefits. Adequate energy is present in conventional flywheel storage systems to provide more power for a shorter duration. A flywheel designed for 125kw for 16 seconds stores enough energy to provide 2MW for 1 second. To provide high discharge for very short durations, the generator and power electronics must be configured such that the power from the stored energy can be realized. Higher speed flywheels allow the generator to be much smaller, minimizing its size and cost. This Phase I will focus on developing a conceptual design for a pulsed power flywheel system. The focus of this effort will be on the motor/generator design and the power electronics design.
Benefits: Phase 1 will show if Flywheel Energy Storage Systems for pulsed power applications can indeed deliver expected advantages in performance, size and cost over conventional technologies. In addition to use on Navy vessels for pulsed power, a significant potential in rail station power exists. In subway stations this type of flywheel can recover and discharge the energy from trains entering and leaving the station, significant reducing power consumption as well as infrastructure investment and maintenance.