Electrification of non-tactical vehicle fleets offers the potential for energy security and greenhouse gas reduction for the U.S. Department of Defense (DoD). This project explores how 40 light and medium duty plug-in electrical vehicles (PEVs), deployed at the Los Angeles Air Force base (L.A. AFB), can optimally charge and discharge to provide grid reliability services. Bi-directional use (charging and discharging) is of interest because of intermittency in the supply side arising from the integration of renewable load resources. The PEVs will be tested to characterize the range of capabilities of all-electric fleets. The highly complex task of scheduling charging and discharging of vehicles will be optimized to minimize energy costs while maximizing participation in ancillary services (AS) markets. Receipt and fast response to grid instructions as well as settlement of revenues from grid service provision will be enabled through use of the OpenADR 2.0b protocol and tested to verify the speed of compliance. The integration of PEVs into the wider base energy system will be analyzed to examine their potential role in base microgrids. The extension to microgrids bridges this project to another key DoD security objective involving energy security through isolated microgrids.