In May 2010, Lockheed Martin was awarded a $3.5 million contract with the U.S. Air Force to build an intelligent microgrid prototype that adds renewable energy to an existing, diesel-powered mobile electric grid to reduce fuel consumption by at least 15 percent. The system can operate in an independent mode or in conjunction with other elements of the larger grid. The system can also shed lower-priority loads in the event that there is insufficient generation, such as when a generator goes offline, to allow high-priority functions such as the command center to continue operations. Within 18 months, Lockheed Martin built and successfully demonstrated the feasibility and benefits of its microgrid system. The Air Force is currently evaluating where to install the prototype for more extensive testing.