MEMS device generates power from body heat

April 29, 2010 By Lisa Zyga, feature
A prototype of the thermoelectric power generator assembled in a ceramic package and placed next to a Singapore ten-cent coin. Image credit: Jin Xie, et al.

( -- In an attempt to develop a power source that is compact, environmentally friendly, and has an unlimited lifetime, a team of researchers from Singapore has fabricated an energy harvesting device that generates electricity from body heat or any environment where there is a temperature gradient. Their device, called a thermoelectric power generator, attaches to the body and generates a power output of a few microwatts, which could be useful for powering implanted medical devices and wireless sensors.

The researchers, Jin Xie and Hanhua Feng from Institute of Microelectronics, A*STAR, Singapore’s government Agency for Science, Technology and Research, along with Chengkuo Lee from the National University of Singapore, have published their study in a recent issue of the Journal of Microelectromechanical Systems.

The entire generator consists of a chip with a size of 1 x 1 cm2, which holds more than 30,000 thermocouples. The thermocouples, when arranged in groups called thermopiles, detect a temperature difference between the hot and cold junctions and produce a voltage. With a temperature difference of 5K, the device can generate a voltage of 16.7 volts and a of 1.3 microwatts. The researchers hope that future improvements to the device could increase the power output to several microwatts. By accumulating this energy over time, it could be used to prolong the battery life of such as pressure sensors, and also recycle heat generated from the devices during operation. By powering the wearer’s medical implants, this technology could enable patients to avoid difficult, high-cost battery replacement methods.

Although similar devices have previously been developed that generate electricity from , the new makes several improvements that increase its overall energy efficiency. For example, the researchers incorporated vacuum cavities, a heat-sink layer, and a peripheral cavity, which are aimed at increasing the temperature difference between the side of the generator touching the body and the side exposed to ambient (cooler) air. The greater the temperature difference between the two sides of the generator, the greater the output voltage.

“The advantages include (1) top and bottom vacuum cavities are created to maximize the between the two junctions of the thermocouples; (2) a heat sink layer is on the cold side of the device to effectively disperse heat from the cold side of the device to ambient air; and (3) a peripheral cavity is designed to cut off heat from the surrounding silicon substrate, so that cold junctions of thermocouples at the rim edge of the device area are not affected by the heat coming from the surrounding silicon,” Xie explained to

As Xie added, another advantage of the new thermoelectric power generator is that it is CMOS-compatible, meaning it can be fabricated in normal CMOS manufacturing lines. This feature allows the generator to serve as a novel on-chip power source for self-powered CMOS and MEMS devices that have low power consumption requirements.

Explore further: Wireless EEG system self-powered by body heat and light

More information: Jin Xie, Chengkuo, and Hanhua Feng. “Design, Fabrication, and Characterization of CMOS MEMS-Based Thermoelectric Power Generators.” Journal of Microelectromechanical Systems, Vol. 19, No. 2, April 2010.


Related Stories

Wireless EEG system self-powered by body heat and light

April 9, 2008

In the framework of Holst Centre, IMEC has developed a battery-free wireless 2-channel EEG (electroencephalography or monitoring of brain waves) system powered by a hybrid power supply using body heat and ambient light. The ...

Self-powered sensors

February 11, 2010

It can be inconvenient to replace batteries in devices that need to work over long periods of time. Doctors might have to get beneath a patient’s skin to replace batteries for implanted biomedical monitoring or treatment ...

A traveling-wave engine to power deep space travel

September 17, 2004

A University of California scientist working at Los Alamos National Laboratory and researchers from Northrop Grumman Space Technology have developed a novel method for generating electrical power for deep-space travel using ...

Energy-autonomous sensors for aircraft

October 1, 2009

Aircraft maintenance will be easier in future, with sensors monitoring the aircraft skin. If they discover any dents or cracks they will send a radio message to a monitoring unit. The energy needed for this will be obtained ...

Recommended for you

Electrode shape improves neurostimulation for small targets

April 24, 2018

A cross-like shape helps the electrodes of implantable neurostimulation devices to deliver more charge to specific areas of the nervous system, possibly prolonging device life span, says research published in March in Scientific ...

China auto show highlights industry's electric ambitions

April 22, 2018

The biggest global auto show of the year showcases China's ambitions to become a leader in electric cars and the industry's multibillion-dollar scramble to roll out models that appeal to price-conscious but demanding Chinese ...

Robot designed for faster, safer uranium plant pipe cleanup

April 21, 2018

Ohio crews cleaning up a massive former Cold War-era uranium enrichment plant in Ohio plan this summer to deploy a high-tech helper: an autonomous, radiation-measuring robot that will roll through miles of large overhead ...

How social networking sites may discriminate against women

April 20, 2018

Social media and the sharing economy have created new opportunities by leveraging online networks to build trust and remove marketplace barriers. But a growing body of research suggests that old gender and racial biases persist, ...

Virtually modelling the human brain in a computer

April 19, 2018

Neurons that remain active even after the triggering stimulus has been silenced form the basis of short-term memory. The brain uses rhythmically active neurons to combine larger groups of neurons into functional units. Until ...


Adjust slider to filter visible comments by rank

Display comments: newest first

3.2 / 5 (5) Apr 29, 2010
Given the aging population, we could put these on all the menopausal women and power the planet with hot flashes!
not rated yet Apr 29, 2010
haha!! That was good! ^^

This is a cool article, hopefully the device will advance so it could charge phones and other devices quickly.
1 / 5 (3) Apr 29, 2010
They should attach these to chickens in slaughter houses as they grow up or what ever, ... on people in jails, i guess just take advantage of all weak life forms with these.
5 / 5 (3) Apr 29, 2010
They should attach these to chickens in slaughter houses as they grow up or what ever, ... on people in jails, i guess just take advantage of all weak life forms with these.

Is this how the machines did it in The Matrix?
not rated yet Apr 30, 2010
They should attach these to chickens in slaughter houses as they grow up or what ever, ... on people in jails, i guess just take advantage of all weak life forms with these.

Is this how the machines did it in The Matrix?

That is specifically, precisely, exactly what they did. Now all we need is an AI smart enough to put two and two together and we're set to go.
not rated yet Apr 30, 2010
If NASA applied this technology to plasma contactor probes on the Z1 segment of the ISS; a constant source of amplified electrical power could be utilized only limited by the surface area of the total panelling and outer hull.

As it stands the power is dissipated into a phantom loop which seems a little wasteful for what hazards space can hold.
not rated yet Apr 30, 2010
My only concern is the "heat sink" they're talking about on the outside, allowing the heat to disperse in the ambient air. Wouldn't that make you feel cold? Who would wear a sweater that actually pulled away their body heat. Sure, maybe in Africa, but solar panels would work well there too. I'd be a little cautious of this one.
not rated yet May 02, 2010
slap a few of these puppies on a cpu and whola!!!
not rated yet May 03, 2010
What if the air's hotter than 37°C? Would it discharge or maybe generate extra heat next to the skin?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.