New approaches for renewable energy management in autonomous marine vehicles

The current powering limitations of the autonomous underwater vehicles make necessary the design of energy packs that can offer prolonged energy during operation. This paper presents an analysis of the operational values of the energy pack considered in autonomous underwater vehicles with extended endurance capability. The hardware, software and external conditions that contribute to the power consumption are considered under a range of different operational scenarios. The power consumption of the hardware used in different missions due to, for example, sensors, propulsion unit, etc., together with the energy pack characteristics definition are considered. The approach leads the development of condition-based maintenance management strategies for underwater operations together with the optimization of the battery life-cycle as a function of charge/discharge uses. A real case-study is presented based on the ENDURUNS European project, where a fuel cell is used as a primary power source, being responsible for re-charging the Li-ion battery stack onboard when required.