Innovations in energy harvesting : A survey of low-power technologies and their potential

Nowadays low-power energy harvesting technologies represent the most sustainable and reliable alternative to traditional batteries that convert ambient energy from chemical reactions, vibrations, magnetic fields, and moisture into usable electrical energy for compact and self-sufficient electronic devices. However, a significant research gap into assessing the reliability, efficiency, and practical deployment of these technologies in various applications still exists. This article encompasses a comprehensive review of different types of electrochemical, kinetic, capacitive, inductive, piezoelectric, and moisture-based energy harvesting techniques. Each method is investigated with respect to their fundamental physical concepts. Thus, a critical discussion of the scientific evolution and functional mechanisms of each technology along with their applications and output characteristics is presented. Based on output characteristics, applications of these energy harvesting techniques in portable electronics, medical implants, wireless sensor networks, industrial monitoring systems, and smart infrastructure are examined in detail. Key challenges, including limited energy conversion efficiency, material constraints, and economic feasibility, are addressed to highlight current limitations. By identifying future research directions and emerging trends, this study highlights the potential of low-power energy harvesting technologies to provide sustainable and reliable energy solutions for several low-power electronics.