Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Energy News .




ENERGY TECH
New material harvests energy from water vapor
by Anne Trafton, MIT News Office
Cambridge MA (SPX) Jan 14, 2013


The new film is made from an interlocking network of two different polymers. One of the polymers, polypyrrole, forms a hard but flexible matrix that provides structural support. The other polymer, polyol-borate, is a soft gel that swells when it absorbs water. To view a video of the new film please go here.

MIT engineers have created a new polymer film that can generate electricity by drawing on a ubiquitous source: water vapor. The new material changes its shape after absorbing tiny amounts of evaporated water, allowing it to repeatedly curl up and down. Harnessing this continuous motion could drive robotic limbs or generate enough electricity to power micro- and nanoelectronic devices, such as environmental sensors.

"With a sensor powered by a battery, you have to replace it periodically. If you have this device, you can harvest energy from the environment so you don't have to replace it very often," says Mingming Ma, a postdoc at MIT's David H. Koch Institute for Integrative Cancer Research and lead author of a paper describing the new material in the Jan. 11 issue of Science.

"We are very excited about this new material, and we expect as we achieve higher efficiency in converting mechanical energy into electricity, this material will find even broader applications," says Robert Langer, the David H.

Koch Institute Professor at MIT and senior author of the paper. Those potential applications include large-scale, water-vapor-powered generators, or smaller generators to power wearable electronics.

Other authors of the Science paper are Koch Institute postdoc Liang Guo and Daniel Anderson, the Samuel A. Goldblith Associate Professor of Chemical Engineering and a member of the Koch Institute and MIT's Institute for Medical Engineering and Science.

Harvesting energy
The new film is made from an interlocking network of two different polymers. One of the polymers, polypyrrole, forms a hard but flexible matrix that provides structural support. The other polymer, polyol-borate, is a soft gel that swells when it absorbs water.

Previous efforts to make water-responsive films have used only polypyrrole, which shows a much weaker response on its own. "By incorporating the two different kinds of polymers, you can generate a much bigger displacement, as well as a stronger force," Guo says.

The film harvests energy found in the water gradient between dry and water-rich environments. When the 20-micrometer-thick film lies on a surface that contains even a small amount of moisture, the bottom layer absorbs evaporated water, forcing the film to curl away from the surface.

Once the bottom of the film is exposed to air, it quickly releases the moisture, somersaults forward, and starts to curl up again. As this cycle is repeated, the continuous motion converts the chemical energy of the water gradient into mechanical energy.

Such films could act as either actuators (a type of motor) or generators. As an actuator, the material can be surprisingly powerful:

The researchers demonstrated that a 25-milligram film can lift a load of glass slides 380 times its own weight, or transport a load of silver wires 10 times its own weight, by working as a potent water-powered "mini tractor." Using only water as an energy source, this film could replace the electricity-powered actuators now used to control small robotic limbs.

"It doesn't need a lot of water," Ma says. "A very small amount of moisture would be enough."

Generating electricity
The mechanical energy generated by the material can also be converted into electricity by coupling the polymer film with a piezoelectric material, which converts mechanical stress to an electric charge. This system can generate an average power of 5.6 nanowatts, which can be stored in capacitors to power ultra-low-power microelectronic devices, such as temperature and humidity sensors.

If used to generate electricity on a larger scale, the film could harvest energy from the environment - for example, while placed above a lake or river. Or, it could be attached to clothing, where the mere evaporation of sweat could fuel devices such as physiological monitoring sensors. "You could be running or exercising and generating power," Guo says.

On a smaller scale, the film could power microelectricalmechanical systems (MEMS), including environmental sensors, or even smaller devices, such as nanoelectronics. The researchers are now working to improve the efficiency of the conversion of mechanical energy to electrical energy, which could allow smaller films to power larger devices.

.


Related Links
Massachusetts Institute of Technology
Powering The World in the 21st Century at Energy-Daily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ENERGY TECH
A new point of reference for offshore energy development
Austin TX (SPX) Jan 10, 2013
A new Department of Energy research facility could help bring the U.S. closer to generating power from the winds and waters along America's coasts and help alleviate a major hurdle for offshore wind and ocean power development. Will Shaw, an atmospheric scientist at DOE's Pacific Northwest National Laboratory, describe plans for the facility at a talk at the 93rd American Meteorological So ... read more


ENERGY TECH
First world atlas on renewable energy launched

Major cuts to surging CO2 emissions are needed now, not down the road

Three new state-of-the-art power plants improve efficiency, reduce emissions

Energy independence for India?

ENERGY TECH
Fracking: A Boom or Bust Decision for New York

Angola grants 116 visas a day to Chinese citizens

Brunei to seek S. China Sea code of conduct

British military making Falkland plans: report

ENERGY TECH
Algonquin Power Buys 109 MW Shady Oaks Wind Power Facility

British group pans wind farm compensation

GE and International Consortium Buys 32 Wind Farms in France

Tax credit extension a reprieve for wind

ENERGY TECH
True Green Capital Management Brings 12.3MW of Solar Energy to Joint Base McGuire-Dix-Lakehurst

A Sunny Future for Mexico

Arista Power Announces US Government Agency Order For a Mobile Renewable Power Station

Renewable energy target in doubt as roadmap launched

ENERGY TECH
Malaysia nuclear plan delayed: official

UAE, Argentina sign civil nuclear agreement

Bangladesh PM to ink $1.5bn arms, nuclear deals in Russia

Indian minister says Areva nuclear deal is close

ENERGY TECH
Tree seeds offer potential for sustainable biofuels

Engineered algae seen as fuel source

Lithuanians recycle Christmas trees into biofuel

Germany Helps Ukraine Develop Biofuel Production

ENERGY TECH
Mr Xi in Space

China plans manned space launch in 2013: state media

China to launch manned spacecraft

Tiangong 1 Parked And Waiting As Shenzhou 10 Mission Prep Continues

ENERGY TECH
Global warming beneficial to ratsnakes

Climate laws advancing in many countries: survey

Urgent CO2 cuts may spare millions hardship: report

US study warns of extreme heat, more severe storms




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement