Energy security and reliability are critical for the Department of Defense (DoD) mission continuity. Microgrids with low cost, large-scale energy storage systems (ESS) have potential to enhance energy security on military installations by facilitating integration of more renewable energy and reducing single-point-of-failure vulnerabilities associated with tradition electric service and back-up generators

ESTCP is currently funding a project titled “Zinc Bromide (Zn/Br) Flow Battery Installation for Islanding and Backup Power Project” (EW-201242), that is demonstrating the energy security and cost benefits of implementing a Zn/Br flow battery-based ESS at Marine Corps Air Station (MCAS) Miramar.

Integration of advanced Zn/Br Battery and Intelligent Power and Energy Management (IPEM) microgrid control technologies coupled with Miramar’s infrastructure will provide energy security, islanding capability, and reduced costs. Success is being defined by the ability to peak shave and island a building circuit for 72 hours. Islanding duration is directly related to 3 main factors: battery energy capacity, photovoltaic penetration, and load reduction.

The demonstration connects Miramar’s buildings to the ESS, enabling the buildings to receive power while off-grid or "islanded" when operating with the ESS and renewable energy system under controlled conditions. The demonstration integrates Primus Power's Zn/Br flow battery with Miramar's renewable energy (RE) sources with Raytheon's IPEM technology providing monitoring and control of the overall system. Prior to installing the system at Miramar, the National Renewable Energy Laboratory conducted testing of the power electronics and controls at the Energy Systems Integration Facility (ESIF) to characterize system behavior and troubleshoot control settings.

Performance data is currently being collected for total energy stored and peak power offset. The demonstration to “island” a building circuit is anticipated to take place in the Spring/Summer of 2016.