Ionocaloric cooling: a new technology under development in the US
A cooling technique using liquid-to-solid phase change fcould be an alternative to vapour compression systems, according to researchers at the University of Berkeley.
At the end of December, an article published in the renowned journal Science was widely reported in the scientific and general press.
In their experiment, the researchers used ethylene carbonate and a salt made up of sodium and iodine. They have developed a refrigeration system using this material. The passage of a current through the system causes a displacement of ions, which changes the melting point of the material; when the latter melts, it absorbs heat from the environment, and when the ions are removed and the material solidifies, it releases heat. Because of the role of ions in the system, the cycle has been dubbed the “ionocaloric cycle” by the team of Berkeley researchers.
Initial experiments have shown a temperature change of 25°C using less than one volt, a temperature lift greater than that achieved by other caloric technologies.
According to the Berkeley researchers, this technique could even induce a carbon-negative balance. Indeed, the ethylene carbonate used for the experiment can be produced using carbon dioxide during its manufacture.
The work of this team will continue in the coming months to determine how this technique could be improved. It is indeed necessary to check whether it can achieve high cooling powers and to evaluate its performance.
The ionocaloric cooling cycle has been granted a provisional patent.
For more information on other caloric cooling technologies, see the latest IIR Informatory Note on caloric cooling.
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