Demonstrating the Benefits of Long-Duration, Low-Cost Flow Battery Storage in a Renewable Microgrid
Benjamin Lavoie | Amerseco, Inc.
The objective of this project is to assess, demonstrate, and validate the operational effectiveness of flow battery storage and quantify the extent to which this technology could replace or significantly reduce the need for diesel generators (DGs), while advancing the state of the art of flow battery storage technology. The project will fulfill this work through analytical modeling, implementation at demonstration host site(s), and an assessment of the opportunity for widespread deployment throughout the Department of Defense (DoD).
In flow batteries, unlike lithium-ion (Li-ion) batteries, liquid electrolyte is stored in tanks external to the cell stack where chemical reactions occur, allowing the power and energy capacities of flow battery systems to be scaled and configured independently. This results in systems capable of longer discharge durations that better support microgrid operation in the event of extended utility grid outages. Other benefits include negligible energy capacity degradation over system life, safety advantages, and greatly reduced thermal management requirements, despite having notably lower round-trip efficiencies and a larger footprint compared to Li-ion systems.
The technology will improve resiliency to utility disturbances as compared to the baseline diesel microgrid. This battery-based solution will add a new level of redundancy and improve the effectiveness of a site’s microgrid capabilities by providing a seamless transition to island operation, reducing the reliance on continuous diesel generation, managing supply with demand within the microgrid, and improving power quality. The energy capacities of flow battery systems will also create significant opportunity to generate value from services provided to the user, local utility, and Independent System Operator (ISO) during non-outage periods. Modeling efforts will help identify desirable locations in which to demonstrate these benefits, appropriate system design, and reliability improvement characterization. Successful demonstration projects will enhance the ability to deploy these solutions to other sites across DoD.