Energy harvesting for the implantable biomedical devices: issues and challenges

Table 2 Comparison between the energy harvesting methods and there challenges

Energy harvesting method	Technique		Reference	Generated power	Advantage	Disadvantage
Human energy harvesting	Kinetic energy	Piezoelectricity	[14]	1 W	- No separate voltage source	- Difficult to integrated with Micro-system
			[15]	8.3 & 1.3 mW	-Voltage of 2–12 volts
			[17]	2.3 mW	-Voltage of 2–12 volts
			[19]	4.8 mW	-No mechanical stops
			[20]	1.2 mW	-No mechanical stops
			[21]	1.81 mW	-Highest energy density
		Electrostatic generator	[23]	8 μW	-Easier to integrate with electronics and micro-systems	- Separate voltage source needed
			[24]	58 μW
			[26]	80 μW
			[27]	40 μW	-Voltage of 2–12 volts	- Mechanical stops needed
			[28]	60 μW	-Voltage of 2–12 volts	- Mechanical stops needed
		Magnetic induction generator	[33]	400 μW	No separate voltage source	-Maximum voltage is 0.1 volts
			[34]	10 μW	No mechanical stops	-Difficult to integrate with micro-systems
			[35]	0.3 μW	No mechanical stops	-Difficult to integrate with micro-systems
			[36]	3.9 μW		-Energy generated only during walking
	Thermal energy		[39]	1.5 μW		Quite low power harvesting
			[40]	1 μW
			[41]	30 μW
Environment energy harvesting	Solar energy		_	_		Not suitable for implanted devices
	Infrared radiation		[43]	4 mW	High power	Large dimension
	Wireless Harvest. energy	Ultrasonic	[48]	100 pW		Low power harvesting
		Ultrasonic	[49]	21.4 nW		Low power harvesting
		Capacitive	_	_		For far range distance and having big size
		Inductive link	[57]	11 mW	High data rate and power transmission and batteries no needed	Limited carrier frequency due to tissue absorptions
			[72]	150 mW
			[73]	10 mW
			[74]	50 mW
			[58]	22 mW

ISSN: 1475-925X