Compressor-Free Refrigerator

Scientists from Penn State University have designed the future of refrigerators and other cooling devices through magnetic field refrigeration. The investigation pertaining to electrically induced heat effects of some ferroelectric polymers might remove electrically powered refrigerators and their compressors and coils. The researchers are focusing on ferroelectric polymers that exhibit temperature changes at room temperature under an electrical field.



Professor Qiming Zhang (Credit: Pennsylvania State University )
Professor Qiming Zhang
(Credit: Pennsylvania
State University )

“This is the first step in the development of an electric field refrigeration unit,” explained Professor Qiming Zhang. “For the future, we can envision a flat panel refrigerator. No more coils, no more compressors, just solid polymer with appropriate heat exchangers.” The polarpolymers that are used in testing include poly (vinylidene fluoride-trifluoroethylene) and poly (vinylidene fluoride-trifluoroethylene) chlorofluoroethylene.

Zhangs’s method changes the form of the polarpolymer from disorganized to organized when positioned in an electric field. The molecules of the polarpolymer are usually disordered and when electricity is passed through, the molecules grow to be highly ordered. This then disperses heat and the material becomes colder. However, if the electricity is switched off, the polarpolymer returns to its disorganized state and eventually increases its temperature to become hot.

Repetitive randomizing and rearranging of the material, in addition with a suitable heat exchanger, could provide a wide range of heating and cooling temperatures. Researchers estimate a difference of 22.6 degrees Fahrenheit (12.5 degree Celsius) between the highest and lowest temperatures.

Current refrigeration and cooling systems, such as air conditioners, are designed to utilize the change in density of gases when set to different pressures. These coolants are both harmful to humans and the environment. A previously used coolant was Freon, which is a banned chlorofluorocarbon due to the negative effects it had on the ozone layer. The current day coolants are relatively safer for humans and the environment, but still have high energy consumption from compressors and an excessive amount of heating coils.

Using the new system, the environment will not be polluted and destroyed by gasses and it can also be used around humans safely. Other than air conditioners and refrigeration units, the technology can be applied to heating or cooling of clothing, cooling of protective gear for fire fighters, heating of mittens, socks or shoes, and even cooling of mascot and cartoon character costumes. An additional application would be in electronics, where tiny amounts of the polymers could efficiently lower the temperature of over-heated circuit boards and thus tolerating closer packing, and in the process producing miniature devices.

TFOT has previously written about refrigerators which cool future computers which is a miniature refrigeration system, small enough to fit inside laptop computers. You can also check out our article about IBM’s nano-water cooled chips where tiny pipes of water can be used to cool next generation PC chips.

Additional information on this new design can be obtained at Penn State University’s website.