This paper presents a novel corrosion-based energy harvester designed for long-term operational deployments in marine infrastructure monitoring. A statistical approach is utilized to characterize the output power, and the results are applied as the basis for designing a complimentary low-power sensor node. Furthermore, statistical analyses are performed on the sensor node operation to ensure robust operation over a range of design and environmental parameters. This paper concludes with a method for estimating the volumetric size of the active component in the energy harvester for long-term operation by analyzing the power consumption of the power electronics.