The U.S. Air Force unveiled Friday a fleet of plug-in electric vehicles equipped to return electricity to the grid as needed.

The fleet of 42 vehicles is located at the Los Angeles Air Force Base in California (LAAFB) and includes both pure electric vehicles as well as PHEV. Of these 42 vehicles, 36 have been equipped with V2G technology, allowing the vehicle to either charge from or return electricity to the grid.

Princeton Power Systems said it designed and delivered a fleet of bi-directional electric vehicle charging stations that can both rapidly charge the passenger vehicles and provide grid-support services back to the electric utility and grid operator.

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Thirteen CHAdeMO-compliant fast-charging stations have been installed and are based on Princeton Power Systems’ UL-Certified bi-directional multi-port converter; the GTIB-30. The new charging station products, named the CA-15 and CA-30, are capable of 15 kilowatt and 30 kilowatt charging rates respectively.

“The Department of Defense and Princeton Power Systems share the view that electric vehicle fleets can have long-term cost, logistics, fuel diversity, and environmental benefits,”said Darren Hammell, Chief Strategy Officer and Co-Founder, Princeton Power Systems. “In conjunction with the fast-charging, bi-directional CA-15 charging stations, the vehicles at the Los Angeles Air Force Base also can provide valuable services to the electric grid, further increasing the economic and environmental sustainability of this unique solution.”

Electric vehicle OEMs and third-party fleet-management software aggregators worked with Princeton Power to develop the LAAFB solution, enabling the vehicles to compete in the electrical utility ancillary service markets and provide energy services to the Department of Defense (DOD) facilities. LAAFB said the ancillary service revenues will partially offset the EV fleet lease expense, while also providing the potential to improve energy security on base.

“We absolutely couldn’t have done this without our federal, state and private partners,” said Miranda Ballentine, assistant secretary of the Air Force for installations, environment and energy. “The shared investment and commitment by our partners illustrates that innovations such as this have value not only to the Air Force and Department of Defense, but to the nation as a whole.”

Princeton Power Systems explained during normal usage, the charging stations will charge the electric vehicles directly from the electric grid, enabling LAAFB personnel to utilize the electric vehicles as transportation within the base and the region. When called upon to support a vehicle-to-grid request, the electric vehicle’s on-board battery can be discharged directly into the grid. The rate of charging and discharging, and communication with the car and the grid, are all managed by the CA-15 charging station, meeting all local and national grid-interconnect codes.

LAAFB added in addition to supporting the efficiency and reliability of the distribution system, the charging station and vehicle can provide demand response, VAR support, frequency regulation, and other operating modes.