Table 1.

Overview of wearable energy harvesting technologies [35,49].

Name	Working Principle	Energy Source	Optimal Load	Output Power (mW·cm−2)	Power Supply
Piezoelectric	Piezoelectric effect and electrostatic induction	Biomechanical energy	kΩ~MΩ	<10−2	Instantaneous AC
Triboelectric	Triboelectric effect and electrostatic induction	Biomechanical energy	MΩ	10−2~10−1	Instantaneous AC
Thermoelectric	Seebeck effect	Heat energy	Ω	<10−3	Continuous DC
Photovoltaic	Photovoltaic effect	Sunlight	Ω	1~10	Instantaneous DC
		Indoor light		10−3~10−1
Biofuel	Biomolecule catalytic redox	Biochemical energy	Ω	10−2~1	Instantaneous DC