Long-Duration Energy Storage

Definition

Battery Energy Storage Systems (BESS) use electricity to drive a reversible chemical reaction to store power. This process is then reversed to inject power into a system.

There are two main components to a battery system. The batteries and the inverter/charge controller that discharges/charges the batteries. Output of a BESS is defined by two major characteristics: power and capacity. Power is defined as the instantaneous energy that is moving into or out of the BESS, usually noted as kW or MW. Capacity is the amount of energy that the BESS can hold, usually noted as kWh or MWh.

USAF Relevance

BESS can store power produced by other connected sources, such as a power plant on the electric grid or onbase generation source and discharge the power later to supplement primary sources. The ideal application for BESS on military installations is to be implemented into a system with both dispatchable generation sources (e.g. diesel generator for hardening or stability) and a renewable (intermittent, to provide low-cost fuel) generation source for longer-term operation. The BESS will both make the renewables less variable as well as smooth the generator output to match load. BESS have multiple value streams, such as providing peak shaving or frequency regulation. Some regulatory markets allow for batteries to be included in ancillary markets – providing power between a buyer and seller of power during congested areas of the grid. To increase the value of a BESS, revenue stacking is common – allowing additional revenue streams with varying uses of the BESS.

Potential Sites

• Vandenberg SFB
• Eareckson AS
• Joint Base McGuire-Dix-Lakehurst
• Offutt AFB
• Tyndall AFB