Energy Harvesting Techniques Enabling Self-Powered IoT Devices

Abstract

The swift expansion of the Internet of Things (IoT) has heightened the difficulty of supplying power to billions of distributed, low-energy devices. Traditional batteries impose restrictions on longevity, scalability, and sustainability. Energy harvesting (EH) facilitates self-powered or energy-autonomous IoT nodes by transforming ambient energy—mechanical, solar, wind, thermal, radio-frequency (RF), and sound—into electrical energy. This concise review outlines the fundamental EH mechanisms, architectures, transducers, power management techniques, storage solutions, and security issues pertinent to IoT. The focus is on practical trade-offs, market readiness, and prospective research avenues aimed at achieving sustainable and secure IoT and Internet of Nano-Things (IoNT) systems.

Introduction

The Internet of Things (IoT) enables connected sensing and control across many sectors, but its major limitation is power supply due to battery constraints, maintenance costs, and environmental impact. Energy harvesting (EH) offers a sustainable solution by extending battery life or enabling battery-free, self-powered IoT devices.

Two main EH architectures are used: Harvest–Store–Use, which stores harvested energy in batteries or supercapacitors to handle intermittent sources but suffers from losses and degradation; and Harvest–Use, which directly powers ultra-low-power devices, reducing cost and losses. Key design considerations include impedance matching, voltage regulation, and maximum power point tracking (MPPT).

Energy harvesting mechanisms include mechanical and vibration energy (notably piezoelectric harvesting), solar energy (the most mature and widely used), and other sources such as wind, sound, radio frequency (RF), and thermal energy. Each source offers different power densities and is suitable for specific environments and applications.

Transducers—such as piezoelectric generators, photovoltaic cells, rectennas, and thermoelectric devices—convert ambient energy into electrical power. Efficient transducer selection and interface design are crucial for achieving energy-positive sensing and autonomous operation.

Effective power management balances harvested energy with consumption using duty cycling, adaptive operation, and low-power modes. Energy storage typically combines batteries and supercapacitors to balance energy density and lifespan. Power Management Integrated Circuits (PMICs) integrate key functions like MPPT, regulation, and storage control, enabling practical EH-based IoT systems.

Security remains a challenge because limited harvested energy restricts traditional cryptographic methods, requiring energy-aware and physical-layer security approaches.

Conclusion

Energy harvesting is a key enabler for sustainable and maintenance-free IoT. Despite challenges such as intermittency, low power density, storage aging, and security risks, advances in materials, transducers, PMICs, and system-level optimization continue to improve viability. Future research will emphasize nanoscale harvesting, highly integrated EH–PMIC–storage platforms, and secure energy-aware protocols, supporting the evolution toward the Internet of Nano-Things (IoNT).

References

[1] Mitcheson, P.D.; Yeatman, E.M.; Rao, G.K.; Holmes, A.S.; Green, T.C. Energy harvesting from human and machine motion for wireless electronic devices. Proc. IEEE2008, 96, 1457–1486. [CrossRef] [2] Priya,S.Advances in energy harvesting using low profile piezoelectric transducers. J. Electroceram.2007, 19, 167–184. [CrossRef] [3] Roundy,S.;WrightP.K.;Rabaey,J.A study of low level vibrations as a power source for wireless sensor nodes. Comput. Commun.2003, 26, 1131–1144. [CrossRef] [4] Beeby,S.P.;Tudor,M.J.;White,N.M.Energy harvesting vibration sources for microsystems applications. Meas. Sci. Technol.2006, 17, R175–R195. [CrossRef] [5] Anton,S.R.;Sodano,H.A.A review of power harvesting using piezoelectric materials (2003–2006). Smart Mater. Struct.2007, 16, R1–R21. [CrossRef] [6] Erturk,A.;Inman,D.J.An experimentally validated bimorph cantilever model for piezoelectric energy harvesting from base excitations. Smart Mater. Struct.2009, 18, 025009. [CrossRef] [7] Li, S.; Crovetto, A.; Peng, Z.; Zhang, A.; Hansen, O.; Wang, M.; Li, X.; Wang, F. Bi-resonant structure with piezoelectric PVDF films for energy harvesting from random vibration sources at low frequency. Sens. Actuators A Phys.2016, 247, 547–554. [CrossRef] [8] Sodano,H.A.;Inman,D.J.;Park,G.A review of power harvesting from vibration using piezoelectric materials. Shock Vib. Dig.2004, 36, 197–205. [CrossRef] [9] Ferrari, M.; Ferrari, V.; Guizzetti, M.; Andò, B.; Baglio, S.; Trigona, C. Improved energy harvesting from wideband vibrations by nonlinear piezoelectric converters. Sens. Actuators A Phys.2010, 162, 425–431. [CrossRef] [10] Khan,F.U.;Qadir,M.U.State-of-the-art in vibration-based electrostatic energy harvesting. Energy Convers. Manag.2016, 126, 1020–1040. [CrossRef]

Copyright

Copyright © 2025 Mrs. Nithiya V., Dr. Manju R., Dr. Bharathi M.. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.