Human body as an energy source

Human body as an energy source

IV. Conclusion

In short, human batteries are coming, it is just a matter of time and research. There is even a greater potential in improving the efficiency of thermoelectric generators . TEG can convert 0.4% of the heat energy into electrical power. If you cover all of your body with TEG you could produce 0.5Watts of energy.

By-Bindhu Reddy Gurram

and Melissa Montes

Under the guidence of Dr.Amar Bhalla and Dr.Ruyan Guo

III. Thermoelectric Energy for

wearable self-powered wireless devices

Source: US Department of Energy, University of California - Berkeley

The wearable wireless sensors powered with human body heat demonstrated that the power obtainable on the human body is large enough to power practical applications.

C. Micromachined Poly-SiGe Thermopile

For cost reduction as compared with commercial ones and much higher output voltage at the same power generation capability.

A. Wireless EEG Headband

B. Power tracking wrist sensor node

• Fabricated recently with surface micromachining technique
• The thermocouples are 2 μm-tall
• Contact resistance between p- and n-SiGe and the interconnecting metal is 40-90 Ωμm2
• A target ZT of 0.096 has been reached for n-SiGe, while for p-type, a ZT of only 0.05 was measured and it is still to be improved twice.

Purpose: to measure the power that can be produced by a wrist TEG in real life at different ambient temperatures.

At 23°C, it produces over 2mW at about 1.8-2V in order to power a EEG system at 0.8mW consumption.

A. Ekuakille, G. Vendramin,"Thermoelectric Generator Design Based on Power from Body Heat for Biomedical Autonomous Devices", IEEE May 29, 2009

The average power production increases by a coefficient of 3 due to 8.5 cm2 radiator featuring small pins and reaches an average power production on man of about 25 μW/cm2 at 22 °C per square cm of the radiator with the available thermoelectric materials showing a ZT of 0.85 and

at a 14-mm thickness of the TEG.

Contents

Electronic module and sensors:

In order to constantly monitor the generated power, the charge storage element, a supercapacitor, must be kept below the limit of its storage capacity.

Performance of the TEG in a real life

Testing of the device has been performed in summer of 2007 at the daytime temperatures reaching 35 °C. While voltage on the charge storage element increases, the transmission rate increases, too, thereby consuming more power and the excess charge.

Most of the time, the transmission rate was

varying in between 1 and 10 s (with entire 0.1 – 100 s

range used by the software), while the voltage

on supercapacitor was kept within the 0.8-1.1 V.

Thermopile

V. Leonov, B. Gyselinckx, "Wearable self-powered wireless devices with thermoelectric energy scavengers", IEEE

I. Introduction

A. Human body as energy source - Inside the body

II. Human body as energy source - Outside the body

A. Power Sources

B. Applications

III. Thermoelectric energy for wearable self-powered wireless devices

A. Wireless EEG Headband

B. Power-tracking wrist sensor node

C. Micromachined poly-SiGe Thermopile

IV. Conclusion

Thermocouple principle

II. Human body as energy source - Outside the body

Source: Department of Materials Science and Metallurgy, University of Cambridge

The related systems need to be wearable and typically consist of sensors, signal conditioning electronics and wireless transmission technology .

B. Applications

A. Power sources

• On body monitoring
• Prosthetics and orthotics
• Portable electronic systems, any device that is powered by a battery.

Promising opportunities: thermal (body device interfacing thermal differential) and kinetic energy (flexion and extension of components - hydraulic control units, structural deformation).

IMEC 'wrist-watch'

I. Introduction

Source: "Energy Harvesting from Human Power", EPSRC

Get the necessary voltage by combining a number of individual generators (thermopiles) over the given area. When each thermopile is connected in series, boost the voltage to a meaningful amount.

The energy produced by the human body is required for important tasks, such as pumping your heart and flexing your muscles, but a lot of it is wasted, primarily as heat, but also through other physical inefficiencies. Almost all of this wasted energy could be captured and turned into electricity, which could then augment or completely replace our reliance on chemical batteries.

"Inner energy", IEE Power Engineer, April 2005

A. Human body as energy source - Inside the body

Most obvious potential power source involve movement (kinetic).

Further potential may be found in human bodily fluid powered micro fuel cells.

A. Ekuakille, G. Vendramin,"Thermoelectric Generator Design Based on Power from Body Heat

for Biomedical Autonomous Devices", IEEE May 29, 2009

Image by Tom Mooring