Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Self-powered sensors

Abstract:
Harvesting electricity from small temperature differences could enable a new generation of electronic devices that don't need batteries.

By David L. Chandler, MIT News Office

Self-powered sensors

Cambridge, MA | Posted on March 10th, 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 systems. Batteries used in devices that monitor machinery, infrastructure or industrial installations may be crammed into hard-to-reach nooks or distributed over wide areas that are often difficult to access.

But new technology being developed by MIT researchers could make such replacements unnecessary.

Soon, such devices could be powered just by differences in temperature between the body (or another warm object) and the surrounding air, eliminating or reducing the need for a battery. They would use new energy-scavenging systems being developed by Anantha Chandrakasan, MIT's Joseph F. and Nancy P. Keithley Professor of Electrical Engineering and director of the MIT Microsystems Technology Laboratories, and Yogesh Ramadass SM '06, PhD '09.

Such a system, for example, could enable 24-hour-a-day monitoring of heart rate, blood sugar or other biomedical data, through a simple device worn on a patient's arm or a leg and powered by the body's temperature (which, except on a 98.6-degree F summer day, would always be different from the surrounding air). A similarly powered system could monitor the warm exhaust gases in the flues of a chemical plant, or air quality in the ducts of a heating and ventilation system.

The concept of harvesting energy from differences in temperature is nothing new. Many technologies for doing so have been developed, including devices NASA has used to power probes sent into deep space (the probes harvest heat from radioactive plutonium). Certain semiconductor materials, by their nature, will produce a flow of electrical current when one side is hotter than the other — or, conversely, will produce a difference in temperature when a current is run through them. Such materials are already used for solid-state coolers and heaters for food or beverages.

The principle was discovered in the 19th century, but only in recent years has it been seriously explored as an energy source. In thermoelectric materials, as soon as there is a temperature difference, heat begins to flow from the hotter to the cooler side. In the process, at the atomic scale this heat flow propels charge carriers (known as electrons or electron holes) to migrate in the same direction, producing an electric current — and a voltage difference between the two sides.

The key to making this principle practical for low-powered devices is to harness as much as possible of the available energy. Chandrakasan and Ramadass have been working to get as close as possible to the theoretical limits of efficiency in tapping this heat energy.

The higher the temperature difference, the greater the potential for producing power, and most such power-generating devices are designed to exploit differences of tens to hundreds of degrees C. The unique aspect of the new MIT-developed devices is their ability to harness differences of just one or two degrees, producing tiny (about 100 microwatts) but nevertheless usable amounts of electric power. The key to the new technology is a control circuit that optimizes the match between the energy output from the thermoelectric material and the storage system connected to it, in this case a storage capacitor. The findings were presented this week at the International Solid State Circuits Conference in San Francisco.

Because thermoelectric systems rely on a difference in temperature between one side of the device and the other, they are not usable for implanted medical devices, where they would be in a uniform-temperature environment. The present experimental versions of the device require a metal heat-sink worn on an arm or leg, exposed to the ambient air. "There's work to be done on miniaturizing the whole system," Ramadass says. This might be accomplished by combining and simplifying the electronics and by improving airflow over the heat sink.

Ramadass says that as a result of research over the last decade, the power consumption of various electronic sensors, processors and communications devices has been greatly reduced, making it possible to power such devices from very low-power energy harvesting systems such as this wearable thermoelectric system.

David Lamb, chief operating officer of Camgian Microsystems, a company that produces a variety of low-power, lightweight semiconductor chips, says that "we believe the wireless sensor products we are developing will all migrate to energy harvesting, as we push their size, weight and power down." He adds that the research of Chandrakasan and Ramadass "is in the critical path of technologies required by companies such as Camgian that are developing next-generation microsystems."

Devices to use this power would in most cases still need some energy storage system, so that the constant slow trickle of energy could be accumulated and used in short bursts, for example to operate a transmitter to send data readings back to a receiver. Different ways of storing the energy are possible, such as the use of ultracapacitors, Ramadass says. "These will play a critical role, in order to build a complete energy harvesting system," he says.

After years of work on these highly efficient energy-scavenging devices, currently funded by a seed grant from the MIT Energy Initiative, Chandrakasan says, "the time has come to find the real applications and realize the vision."

Read part two of this series, "Power from motion and vibrations."

web.mit.edu/newsoffice/2010/power-from-motion-and-vibrations.html

####

About MIT
The mission of MIT is to advance knowledge and educate students in science, technology and other areas of scholarship that will best serve the nation and the world in the 21st century — whether the focus is cancer, energy, economics or literature.

For more information, please click here

Copyright © MIT

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

SEMATECH to Showcase Innovation and Advances in Manufacturing at SEMICON Japan 2014: SEMATECH experts will share the latest techniques, emerging trends and best practices in advanced manufacturing strategies and methodologies November 26th, 2014

Australian startup creates world’s first 100% cotton hydrophobic T-Shirts November 26th, 2014

The mysterious 'action at a distance' between liquid containers November 26th, 2014

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Possible Futures

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Researchers discern the shapes of high-order Brownian motions November 17th, 2014

VDMA Electronics Production Equipment: Growth track for 2014 and 2015 confirmed: Business climate survey shows robust industry sector November 14th, 2014

Open Materials Development Will Be Key for HP's Success in 3D Printing: HP can make a big splash in 3D printing, but it needs to shore up technology claims and avoid the temptation of the razor/razor blade business model in order to flourish November 11th, 2014

Academic/Education

SUNY Poly Student Awarded Fellowship with the U.S. Department of Energy's Postgraduate Research Program: Ph.D. Candidate Accepts Postmaster's Appointment To Conduct Research At Albany NanoTech Complex November 13th, 2014

SUNY Polytechnic Institute Hosts Massive Crowd of More Than 3,000 People Who Attended Community Day Activities Across New York State: CNSE’s ‘NANOvember’ kickoff event highlights New York State’s growing high-tech sector with open house events in Albany, Utica, and Rochester November 3rd, 2014

SUNY Polytechnic Institute Invites the Public to Attend its Popular Statewide 'NANOvember' Series of Outreach and Educational Events October 23rd, 2014

First Canada Excellence Research Chair gets $10 million from the federal government for oilsands research at the University of Calgary: Federal government announces prestigious research chair to study improving oil production efficiency October 19th, 2014

MEMS

MEMS Industry Group's 10th Annual Executive Conference Showcases Rapid Innovation in MEMS/Sensors: Emphasizes Spirit of Collaboration, Supporting First Open-Source Algorithm Community, New Standardization Efforts November 10th, 2014

MEMS & Sensors Technology Showcase: Finalists Announced for MEMS Executive Congress US 2014 October 23rd, 2014

IEEE International Electron Devices Meeting To Celebrate 60th Anniversary as The Leading Technical Conference for Advanced Semiconductor Devices September 18th, 2014

Carbyne morphs when stretched: Rice University calculations show carbon-atom chain would go metal to semiconductor July 21st, 2014

Chip Technology

SEMATECH to Showcase Innovation and Advances in Manufacturing at SEMICON Japan 2014: SEMATECH experts will share the latest techniques, emerging trends and best practices in advanced manufacturing strategies and methodologies November 26th, 2014

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Nanometrics Announces Upcoming Investor Events November 19th, 2014

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Nanomedicine

Vegetable oil ingredient key to destroying gastric disease bacteria: In mice, therapeutic nanoparticles dampen H. pylori bacteria and inflammation that lead to ulcers and gastric cancer November 25th, 2014

Research reveals how our bodies keep unwelcome visitors out of cell nuclei November 24th, 2014

ASU, IBM move ultrafast, low-cost DNA sequencing technology a step closer to reality November 24th, 2014

An Inside Job: UC-Designed Nanoparticles Infiltrate, Kill Cancer Cells From Within November 24th, 2014

Sensors

Lawrence Livermore researchers develop efficient method to produce nanoporous metals November 25th, 2014

Cooling with the coldest matter in the world November 24th, 2014

Canatu Launches CNB In-Mold Film for Transparent Touch on 3D Surfaces –in Cars, Household Appliances, Wearables, Portables November 20th, 2014

UO-industry collaboration points to improved nanomaterials: University of Oregon microscope puts spotlight on the surface structure of quantum dots for designing new solar devices November 20th, 2014

Announcements

SEMATECH to Showcase Innovation and Advances in Manufacturing at SEMICON Japan 2014: SEMATECH experts will share the latest techniques, emerging trends and best practices in advanced manufacturing strategies and methodologies November 26th, 2014

Australian startup creates world’s first 100% cotton hydrophobic T-Shirts November 26th, 2014

The mysterious 'action at a distance' between liquid containers November 26th, 2014

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Energy

Lawrence Livermore researchers develop efficient method to produce nanoporous metals November 25th, 2014

Research yields material made of single-atom layers that snap together like Legos November 25th, 2014

Blu-ray disc can be used to improve solar cell performance: Data storage pattern transferred to solar cell increases light absorption November 25th, 2014

UO-industry collaboration points to improved nanomaterials: University of Oregon microscope puts spotlight on the surface structure of quantum dots for designing new solar devices November 20th, 2014

Events/Classes

SEMATECH to Showcase Innovation and Advances in Manufacturing at SEMICON Japan 2014: SEMATECH experts will share the latest techniques, emerging trends and best practices in advanced manufacturing strategies and methodologies November 26th, 2014

Professional AFM Images with a Three Step Click SmartScan by Park Systems Revolutionizes Atomic Force Microscopy by Automatizing the Imaging Process November 24th, 2014

3rd Iran-Proposed Nano Standard Approved by International Standard Organization November 22nd, 2014

Sustainable Nanotechnologies Project November 20th, 2014

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More












ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE