Sustainable energy harvesting techniques for underwater aquatic systems with multi-source and low-energy solutions

Abstract

Underwater Internet of Things (IoT) systems are essential for monitoring and conserving aquatic ecosystems. These systems are deployed with limited energy resources, harsh environmental conditions and high energy consumption during communication. Standalone solar or wave-based energy harvesting techniques are insufficient because of ecological conditions and variable energy availability. In addition, conventional communication protocols are power-hungry and limit the operation time of underwater nodes. This work introduces a strong, energy-efficient combination of Multi-Source Energy Harvesting Systems and Low-Energy Communication Protocols. The proposed approach will ensure constant energy flow irrespective of the submarine's changing environment by intermixing wave energy with thermal energy, microbial fuel cells, and backup solar systems. The supplementary alternative energy sources avoid the need for batteries, which could result in sustainable operations. Additionally, incorporating low-power communication techniques such as Frequency Shift Keying (FSK) and sleep-wake scheduling significantly reduces energy consumption during data transmission. It is the most power-intensive operation in IoT networks. The proposed work addresses gaps in existing energy harvesting and communication frameworks by optimizing energy generation and consumption. This dual approach enhances the sustainability of underwater IoT systems and improves reliability in diverse and unpredictable aquatic environments. The proposed low-energy communication protocol achieves a transmission success rate of 98.5 %, energy harvesting efficiency of 90 %, and a battery lifetime of over 72 h, optimized for underwater environments.