News • 28.05.2018

New material makes cooling devices more energy-efficient

Environmentally friendly alternatives are systems which use water

For their tests, they coated a conventional heat exchanger (as used in...
For their tests, they coated a conventional heat exchanger (as used in commercial refrigeration equipment) with the new material, in cooperation with colleagues from the Fraunhofer Institute for Solar Energy Systems
Source: Dirk Lenzen

Waste heat from industry can often not be utilised because of its low temperature. With this material, it can be used in environmentally friendly cooling systems for example in the field of building technology.

Cooling devices are considered to be power guzzlers, in which polluting refrigerants are still used, even after the ban on chlorofluorocarbons (CFCs). An environmentally friendly alternative are systems which use water instead. A research team at the Institute of Inorganic Chemistry at Kiel University, together with the Fraunhofer Institute for Solar Energy Systems ISE in Freiburg, has developed a highly-porous material, with which these cooling systems can be operated using less electrical energy than before. Previously-unused waste heat, e.g. from district heating systems, data centres, or heat from solar thermal collectors could be used for that. The results have been published recently in the journal Advanced Materials. 

Data centres in particular are real energy factories: as a side-effect of their operations, high-performance computers produce a lot of heat, and must therefore be cooled continuously. As such, they cause high energy and power costs, while giving off unused waste heat to the environment at the same time – its temperature is too low for other uses. Theoretically, however, this could be used for running energy-efficient cooling systems, which use water as a refrigerant (so called adsorption-driven chillers). To do so, the material used there must be able to absorb a lot of water and regenerate at the lowest possible temperatures. 

Environmentally-friendly and resource-saving cooling

The porous material, developed by Professor Norbert Stock from the Institute of Inorganic Chemistry and his working group, fulfils these requirements. This way parts of the cooling process of adsorption-driven chillers can be operated using only the energy from existing waste heat or solar thermal systems. "This could also make an important contribution to the use of renewable energies," said Stock. For environmentally friendly systems like this the material has two key advantages: "The systems consume less power, and we can produce the material in an eco-friendly manner," explained the inorganic chemist. 

In these so-called adsorption-driven chillers, the cooling effect occurs when ambient heat is extracted by the evaporation of water. The molecules of water vapour are deposited in the cavities of a porous material, called sorbents, i.e. adsorbed by it. In the following regenerative phase the material is dried by applying thermal energy. The stored water molecules are released, liquefy and can be evaporated again in the next cycle. The material can also be used again. 

Highly-porous metal organic frameworks provide ideal interactions

Sorbents used in cooling systems are usually crystalline zeolites or silica gels, which can easily absorb water due to their structure. The research team’s material exhibits particularly good sorption properties: it can absorb a lot of water very quickly, and also release it quickly again - even at a low increase in temperature. The material is thus quickly ready for use again. "This is made possible by the optimal size of the pores in the material, and its perfect interaction with the water molecules," explained Stock. The highly-porous crystal structure of "CAU-10-H" - which is the official name of the material, named after development location, version number and the abbreviation of hydrogen - is an example of a metal organic framework (MOF). They have been tested in a wide range of areas of application in recent years.

From fundamental research to practical application 

The Kiel working group has already been pursuing the discovery of new MOFs for a long time - but previously only as pure fundamental research. For transfer to an industrial application, they worked with colleagues from the Fraunhofer ISE to coat commercially available heat exchangers with their material. "The survey of the heat exchanger under application-related conditions shows the high potential of the material" said Dr Stefan Henninger from the ISE. In the laboratory, the material can already be produced in kilogramme quantities under mild reaction conditions, i.e. at a temperature of 100°C with water as a solvent ("green synthesis"). "In order to produce the material for an industrial use on a larger scale, our next step is to contact other companies," said Stock. They have already applied for a patent for their production method. 

Source: Christian-Albrechts-Universität zu Kiel

related articles:

popular articles:

Thumbnail-Photo: One, two, go: get a new shop window!
27.02.2019   #shop decoration #brand management

One, two, go: get a new shop window!

Magnetic films make it possible

Redecorating an entire shop window in 30 seconds? Yes, that's possible! At the Panorama in Berlin we saw exactly that at the booth of the Pioneer Trading Company. The principle is simple: magnetic films with all kinds of motifs can be ...

Thumbnail-Photo: Power floor: power store
27.03.2019   #pos marketing #in-store marketing

Power floor: power store

Practical examples of amazing flooring designs

Sales promotion is also a matter of the floor. Take the time for some inspiration and discover different designs - from colorful and patterned to natural and neutral - in practical examples that we have put together for you. All projects can also be ...

Thumbnail-Photo: Presentation of goods for convenience at gas stations...
28.02.2019   #product presentation #automated replenishment (software)

Presentation of goods for convenience at gas stations

POS TUNING and ARAL report on a successful multi-partner project

At this year's Annual Conference on Trade and Change in Gas Stations and Convenience Shops, Kristin Kolbe-Schade from POS TUNING and Carsten Biermann from Aral reported on a successful tobacco project which they implemented together with other ...

Thumbnail-Photo: Expert tips: the best flooring options for your retail store...
15.04.2019   #shop building #visual merchandising

Expert tips: the best flooring options for your retail store

Ways to make a great first impression with customers

You need a new look for the flooring in your store – you have many options and they must be considered carefully. Industry experts told us what the different types of flooring from vinyl to carpet all the way to renovation lacquer systems have ...

Thumbnail-Photo: What shop design can look like: Marktscheune in Berghaupten...
18.03.2019   #shop building #brick and mortar retail

What shop design can look like: Marktscheune in Berghaupten

Many wooden design elements, rustic flair, and the Farmer’s Café delight guests

Buy a piece of cake, have a cup of coffee and pick up some fresh vegetables and fruits to take home. Customers can run all of these errands at the Marktscheune (English: Market Barn). The so-called Naturpark-Bauernmarkt (English: Nature Park ...

Thumbnail-Photo: Snipes Reopening in Cologne: Shopdesign goes Hip-Hop...
31.01.2019   #digital signage #shop building

Snipes Reopening in Cologne: Shopdesign goes Hip-Hop

At the end of last year, the Snipes Store on Hohe Strasse in Cologne was reopened.

We attended the pre-opening and were privileged to see the new design in the first customer's eyes. Have fun with the video report!Your iXtenso team ...

Thumbnail-Photo: Show your costumers instant digital content on mirrors...
07.02.2019   #digital signage #brick and mortar retail

Show your costumers instant digital content on mirrors

Mirror mirror on the wall, who's the smartest of them all?

In the interview Jukka Vänskä from Seloy Live is showing us, what customers can do with a digital mirror and why it could benefit retailers. His partner Alexander von Reuterhorn from Fineko Green Technologies ensures a bacteria-free ...

Thumbnail-Photo: Retail holiday decorations: trends for the 2019/20 season...
09.05.2019   #decorative lighting #shop decoration

Retail holiday decorations: trends for the 2019/20 season

"The little affectionate details are always what’s most important." Interview with Annetta Palmisano

Many details or a simple design, artificial light displays or natural light – there are many ways to showcase window displays. Retailers who decorate with a light touch can use the emotional impact on customers and affect retail business ...

Thumbnail-Photo: ISE: big LED displays, digital mirrors and more!...
07.02.2019   #digital signage #decorative lighting

ISE: big LED displays, digital mirrors and more!

The trends of tomorrows audiovisuals and system integrations

iXtenso was at the ISE in Amsterdam and looked around for the latest trends in audiovisual media. We couldn't help but to take snapshots of some of the most beautiful implementations. ...

Supplier

POS TUNING Udo Voßhenrich GmbH & Co KG
POS TUNING Udo Voßhenrich GmbH & Co KG
Am Zubringer 8
32107 Bad Salzuflen
Pioneer Trading Company GmbH
Am Sohlweg 26
76297 Stutensee