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
Temperature-controlled fiber-optic light source with liquid core
20.06.2018 | Leibniz-Institut für Photonische Technologien e. V.
New material for splitting water
19.06.2018 | American Institute of Physics
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
21.06.2018 | Earth Sciences
21.06.2018 | Life Sciences
21.06.2018 | Earth Sciences