Chinese researchers have developed plastic crystals that are alternative cooling materials for fridges.
Almost one-third of the world's electricity is consumed by air conditioners, refrigeration equipment, and heat pumps.
The lead researcher is Bing Li from the Chinese Academy of Sciences' Institute of Metal Research. He believes that the use of plastic crystals could be better for the environment.
Traditional fridges rely on compressing materials to convert gas to liquid. Heat is absorbed by the liquid that converts the liquid back into a gas to repeat the cycle.
These fluids are refrigerants that contribute to global warming despite their efficiency in absorbing and heating heat.
Chlorofluorocarbons (CFCs) contribute to the ozone layer depletion and have been banned. However, its counterpart hydrofluorocarbons (HFCs) are still greenhouse gases.
Policies in developed countries have implemented the reduction of HFCs. However, there are gray areas as there is no specific substitute on what refrigerations and air conditioners will use as chemicals.
Greener alternatives involve temperature-changing solids that respond to external pressure. Powdery plastic crystals have multiple uses that include plastics, paints,and cosmetics.
Li and his colleagues have discovered that plastic crystals can also be used as a refrigerant, in addition to Li storing energy.
Li says that the disordered structure or plastic crystals allow the materials to transform between the ordered and disordered state.
Neopentylglycol, a type of plastic crystal, "has an energy change tens of times greater than other potential solid refrigerants, meaning it has a far greater cooling effect on its surroundings when the same pressure is applied," according to News Scientist.
"We identified plastic crystals as promising materials for solid-state refrigeration," says Li, but the team needs to do more work to reduce heat loss and maximise the energy efficiency of the process in order to match that of existing liquid-to-gas refrigerants.
