An energy storage system is presented. The energy storage system includes a primary energy storage device operatively couplable to a main bus, where the main bus is operatively coupled to a power generation device. Further, the energy storage system includes an auxiliary bus operatively couplable to the main bus and a grid bus. Furthermore, the energy storage system includes a plurality of auxiliary loads operatively coupled to the auxiliary bus and a housing configured to encompass the primary energy storage device, the auxiliary bus, and the plurality of auxiliary loads, where the auxiliary bus is configured to supply power to the plurality of auxiliary loads from the primary energy storage device, the power generation device, a grid, or combinations thereof.