Usually, most of the AUV has the propeller and it is placed in a suitable position for maneuvering in the required direction. For single propeller AUVs, propeller is placed at the aft, and direction is controlled using wings that are placed aft. Energy is a major part of an underwater operation to decide the duration of underwater operation. To increase the duration of the battery, either the energy consumption can be reduced or the efficiency of the propulsion system needs to be improved. Here the possible opportunities to improve the propulsion system using hydrodynamic energy devices are discussed. Though many options are available, based on space availability & speed, a suitable combination of devices can be added. It is recommended to carry out CFD analysis to make sure that proposed devices can bring improvement in the propulsion system before it is implemented.