Harvesting Ambient Environmental Energy for Wireless Sensor Networks: A Survey

Table 8

The comparison of various energy harvesting methods for WSNs.

Energy sources	Voltage; regulation	Energy storage; device needed	The possible applications in WSNs
Photovoltaics	Maybe	Usually	Sensors in outdoors or in where with long time artificial light like the shopping centers, factories, and so forth
Mechanical energy harvesters
Piezoelectric; Electrostatic; Electromagnetic	Yes	Usually	Sensors installed on (or in contact with) moving or working bodies, vehicles, engines, or other vibration or mechanical sources
TEG	Maybe	Usually	Sensors in where existing temperature differs with surroundings like body surface, engine, and so forth
Dynamic fluid energy
Wind harvester	Yes	Yes	Sensors in outdoors or in moving or rotating objects
Flowing water	Yes	Usually	Sensors in the water or with direct contact of water or with automated watering
Acoustic energy	Yes	Yes	Sensors where high level noise exists such as shopping centers, factories, and so forth; the side of objects with high-decibel like engine nacelles
Magnetic field energy	Yes	Usually	Sensors where existing strong magnetic field exists such as power transmission/distribution lines