Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Milestone in magnetic cooling

27.08.2007
The first milestone in magnetic cooling has been achieved. Between 5 and 10 degrees of cooling – this was the success criteria for the first milestone in a project involving magnetic cooling at Risø National Laboratory – Technical University of Denmark (DTU).

And the figure is currently at 8.7°C – this means that a refrigerator at room temperature (20°C) can be cooled to almost 11°C. Of course, this is not quite enough to keep the milk cold, but the project’s test setup also has only the one objective of conducting research in different materials, varying operating conditions and the strength of the magnetic field.

Size is not all that matters!

“The setup is not the largest of its type, but the most important thing is that it ’s easy to exchange parts in the machine. With the knowledge that we gain along the way, we will ultimately be able to build the very best magnetic cooling system,” explains Christian Bahl, a postdoctoral student attached to the project for one year.

More than DKK 21 million in new funding has made it possible to appoint three PhD students this year to work on the MagCool project, and two more PhD students are to be appointed this autumn. Christian Bahl will also be joined by another two postdoctoral students in 2009.

How is a magnetic field used for cooling?

Magnetic cooling technology exploits the fact that when a magnetic material, in this case the element gadolinium, is magnetised, heat is produced as a by-product of entropy. The principle of entropy is that there will always be a constant amount of order/disorder in a substance. When the magnet puts the substance in “order”, it has to get rid of the excess disorder – and this becomes heat. Conversely, when the magnetic field is again removed, the substance becomes cold.

The heat is transferred to a fluid that is pumped back and forth past the substance inside a cylinder. The end that becomes cold will be located inside the refrigerator and the warm end will be outside.

Why magnetic cooling?

It is natural to wonder: Why magnetic cooling? After all, there are decent and also relatively energy-efficient refrigerators on the market. But there are three good reasons why this type of cooling has a future.

First, the technology is potentially more energy-efficient than the alternatives. It only really uses energy to move the magnetic field to and from the magnetic material. The model currently under development produces the magnetic field through a system of powerful blocks of magnets similar to those we use on our refrigerator doors, only stronger. These do not get worn out, and thus do not need replacing, which is very good for the environment.

This leads to the second major benefit, namely the fluid, which could turn out to be just plain water. Consequently, there would not be the same environmental impact as with today’s compressor-based refrigerators. The third great potential difference is the noise level. Bahl expects their demonstration model, which should be ready in 2010, to be practically silent. The opportunities are obvious.

“It is probably not realistic to think that magnetic cooling technology will be used in consumers’ homes right away. Manufacturers have spent too many years streamlining the prices of the existing refrigerators. Initially, it will be about implementation in various types of niche applications – large-scale refrigerating plants, soda machines or places where a noise-free environment is important,” says Bahl, adding, however, that he believes it will ultimately spread to the rest of society.

On a global scale, there are at least ten other teams working on similar projects involving magnetic cooling, but the field has not yet become a major focus area. The concept of magnetic cooling has been known for many years, but using the technology at room temperature is something relatively new.

Collaboration with industry

At Risø’s Department of Fuel Cells and Solid State Chemistry, Senior Scientist Nini Pryds has received a grant of approximately DKK 14 million from the Danish Council for Strategic Research Programme Commission on Energy and Environment. Along with the DKK 7 million that Risø and the three partners – DTU’s Department of Manufacturing and Engineering Management, Sintex and Danfoss – are investing in the MagCool project, it will be possible to develop a prototype.

Sintex has the expertise in permanent magnetic fields, and the company is currently developing the model of magnets that will produce the powerful magnetic field for Risø’s test model. Another objective of the project is to determine whether this technology can pave the way for the super-efficient and environmentally friendly refrigeration machine of the future.

Leif Sonderberg Petersen | alfa
Further information:
http://www.risoe.dk

More articles from Physics and Astronomy:

nachricht Seeing the quantum future... literally
16.01.2017 | University of Sydney

nachricht Airborne thermometer to measure Arctic temperatures
11.01.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>