Demand Smoothing in Military Microgrids Through Coordinated Direct Load Control

In small microgrids and individual branches of a bulk electrical grid, the aggregate electrical load can contain significant and frequent peaks caused by large individual loads. These peaks can reduce overall system efficiencies if generation resources, e.g., diesel generators, are dispatched based on peak demand. This problem is particularly severe in military forward operating base (FOB) microgrids, in which the load profile is dominated by environmental control units (ECUs) that operate under thermostatic control. Leveraging the intrinsic energy storage capabilities associated with large loads such as these ECUs and coordinating their operations across neighboring facilities provides an opportunity to reduce peak demand while maintaining system performance. Using a military FOB microgrid as a use case, this paper presents two direct load control (DLC) algorithms for coordinating ECU operations and reducing peak demand. This coordinated control is demonstrated through simulations and field tests at the U.S. Army's Base Camp Integration Laboratory using novel controller hardware. Both simulation and field tests indicate that the DLC algorithms can reduce peak loads by 25% or more without sacrificing thermal comfort.