Imagine a refrigerator, air conditioner or other compressed gaseous system that has no more coils, compressors and controls. Penn State’s Qiming Zhang is offering that his research is yielding a refrigeration technique that is based in ferroelectric polymers.

Ferroelectric polymers exhibit piezoelectric and pyroelectric effects that are usually encountered in certain single crystals and ceramics. Ziang exploits these new polymers with an approach that uses the change from disorganized to organized that occurs in some polarpolymers when placed in an electric field. The natural state of these materials is disorganized with the various molecules randomly positioned. When electricity is applied, the molecules become highly ordered and the material gives off heat and becomes colder. When the electricity is turned off, the material reverts to its disordered state and absorbs heat. Zhang’s group reports a change in temperature for the material of about 22.6 degrees Fahrenheit. It seems Zhang and his team has discovered a way to manipulate the material so that rather than heat or cool it to acquire electricity they use the electricity to compel the material to heat and cool. Very intuitive research work.

“This is the first step in the development of an electric field refrigeration unit,” says Zhang, distinguished professor of electrical engineering. “For the future, we can envision a flat panel refrigerator. No more coils, no more compressors, just solid polymer with appropriate heat exchangers.”

The Penn State news release lists a few possible applications, heating or cooling of a variety of clothing including cooling of protective gear for fire fighters, heating of mittens and socks or shoes for athletes, sportsmen and law enforcement officers and in electronics, where small amounts of the polymers could effectively cool over heating circuit boards and allow closer packing, and therefore smaller devices. – notably overlooking the air conditioning of electric vehicles. The paper is up at Science Magazine’s August 8, 2008 issue. Zhang’s team includes Bret Neese, graduate student, materials science and engineering; postdoctoral fellows Baojin Chu and Sheng-Guo Lu; Yong Wang, graduate student, and Eugene Furman, research associate.

Thermoelectric devices have been of interest for me for a very long time. Pyroelectricity first turned up in 314 BC in writings of Theophrastus and again in 1707 was “rediscovered” by Johann George Schmidt. So thermoelectric has been of interest, although not very efficient, for a very long time. What makes the Penn State research interesting is “These polymers are flexible and can be used for heating and cooling, so there may be many different possible applications,” said Zhang.

Now we have flexible thermoelectric, with a good range of temperature change. The news release also notes that other compounds have properties that could be used for cooling.

At a very first step this is encouraging news. I’ve thought for a long time that thermoelectric heating and cooling or simply pumping heat is a field in need of support and innovations. One has at last come. I sure hope the power requirements bring good news and that other great minds apply themselves to finding low cost and cheap to run devices that would be simple, efficient and practical. Solid state heating and cooling is based in a great idea centuries old, but the efficiency thing still needs attention. Perhaps a race is finally starting in this field.


Comments

2 Comments so far

  1. yong on April 3, 2009 10:03 PM

    good

  2. nursing schools on November 8, 2010 7:48 AM

    I think one of your advertisements caused my internet browser to resize, you might want to put that on your blacklist.

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