Featured Research

from universities, journals, and other organizations

Environmentally-friendly Cooling With Magnetic Refrigerators Coming Soon

Date:
May 17, 2009
Source:
Imperial College London
Summary:
Scientists are a step closer to making environmentally-friendly 'magnetic' refrigerators and air conditioning systems a reality.

Scientists are a step closer to making environmentally-friendly 'magnetic' refrigerators and air conditioning systems a reality, thanks to new research published May 15 in Advanced Materials.

Magnetic refrigeration technology could provide a 'green' alternative to traditional energy-guzzling gas-compression fridges and air conditioners. They would require 20-30% less energy to run than the best systems currently available, and would not rely on ozone-depleting chemicals or greenhouse gases. Refrigeration and air conditioning units make a major contribution to the planet's energy consumption - in the USA in the summer months they account for approximately 50% of the country's energy use.

A magnetic refrigeration system works by applying a magnetic field to a magnetic material - some of the most promising being metallic alloys - causing it to heat up. This excess heat is removed from the system by water, cooling the material back down to its original temperature. When the magnetic field is removed the material cools down even further, and it is this cooling property that researchers hope to harness for a wide variety of cooling applications.

The technology, based on research funded in the UK by the Engineering and Physical Sciences Research Council (EPSRC), has proved possible in the lab but researchers are still looking for improved materials that provide highly efficient cooling at normal room temperatures, so that the technology can be rolled out from the lab to people's homes and businesses.

They need a material that exhibits dramatic heating and cooling when a magnetic field is applied and removed, which can operate in normal everyday conditions, and which does not lose efficiency when the cooling cycle is repeated time after time.

The new study published May 15 shows that the pattern of crystals inside different alloys - otherwise known as their microstructure - has a direct effect on how well they could perform at the heart of a magnetic fridge. The Imperial College London team behind the new findings say this could, in the future, help them to custom-design the best material for the job.

Professor Lesley Cohen, one of the authors of the paper, explains that by using unique probes designed at Imperial, her team, led by Dr James Moore, was able to analyse what happens to different materials on a microscopic level when they are magnetised and de-magnetised. This enabled the team to pinpoint what makes some materials better candidates for a magnetic fridge system than others.

Professor Cohen, from Imperial's Department of Physics, said: "We found that the structure of crystals in different metals directly affects how dramatically they heat up and cool down when a magnetic field is applied and removed. This is an exciting discovery because it means we may one day be able to tailor-make a material from the 'bottom up', starting with the microstructure, so it ticks all the boxes required to run a magnetic fridge. This is vitally important because finding a low-energy alternative to the fridges and air conditioning systems in our homes and work places is vital for cutting our carbon emissions and tackling climate change."

This new research follows on from another study published by the same Imperial group in Physical Review B last month, in which they used similar probing techniques to precisely measure the temperature changes that occur when different materials are removed from a magnetic field, and to analyse the different ways they occur.

The lead scientist Kelly Morrison found that at the molecular level two different temperature change processes, known as first- and second-order changes, happen simultaneously in each material. The team think that the extent to which each of these two processes feature in a material also affects its cooling capabilities.

Professor Cohen says this means that whilst the majority of research to perfect magnetic refrigeration worldwide has tended to involve analysing and testing large samples of materials, the key to finding a suitable material for everyday applications may lie in the smaller detail:

"Our research illustrates the importance of understanding the microstructure of these materials and how they respond to magnetic fields on a microscopic level," she concluded.

The research was carried out in collaboration with the Ames Laboratory, USA.


Story Source:

The above story is based on materials provided by Imperial College London. Note: Materials may be edited for content and length.


Journal References:

  1. James D. Moore et al. Metamagnetism seeded by nanostructural features of single crystalline Gd5Si2Ge2. Advanced Materials, May 2009
  2. K. Morrison et al. Capturing first- and second-order behavior in magnetocaloric CoMnSi0.92Ge0.08. Physical Review B, 6 April 2009

Cite This Page:

Imperial College London. "Environmentally-friendly Cooling With Magnetic Refrigerators Coming Soon." ScienceDaily. ScienceDaily, 17 May 2009. <www.sciencedaily.com/releases/2009/05/090515083822.htm>.
Imperial College London. (2009, May 17). Environmentally-friendly Cooling With Magnetic Refrigerators Coming Soon. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2009/05/090515083822.htm
Imperial College London. "Environmentally-friendly Cooling With Magnetic Refrigerators Coming Soon." ScienceDaily. www.sciencedaily.com/releases/2009/05/090515083822.htm (accessed July 30, 2014).

Share This




More Earth & Climate News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com
Climate Change Could Cost Billions, According To White House

Climate Change Could Cost Billions, According To White House

Newsy (July 29, 2014) A report from the White House warns not curbing greenhouse gas emissions could cost the U.S. billions. Video provided by Newsy
Powered by NewsLook.com
Climate Change Could Cost Billions According To White House

Climate Change Could Cost Billions According To White House

Newsy (July 29, 2014) A report from the White House warns not curbing greenhouse gas emissions could cost the U.S. billions. Video provided by Newsy
Powered by NewsLook.com
Jane Goodall Warns Great Apes Face Extinction

Jane Goodall Warns Great Apes Face Extinction

AFP (July 29, 2014) The world's great apes face extinction within decades, renowned chimpanzee expert Jane Goodall warned Tuesday in a call to arms to ensure man's closest relatives are not wiped out. Duration: 00:58 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins