Making Refrigerators More Sustainable with Crystal-based Cooling Technology

A new type of crystal could help refrigerators and air conditioners keep us cool without warming the planet.

Refrigerators and air conditioners obtain their cooling power by circulating liquid within the device. The liquid absorbs heat and causes cooling through cycles of evaporation and condensation. However, many such liquids contribute to the greenhouse effect and cause further warming if they leak. now, jenny pringle Researchers at Australia's Deakin University have created a climate-friendly alternative to these liquids using “plastic crystals” – crystals containing molecules that can move enough to make them flexible. Developed.

If enough pressure is applied, these plastic crystals can deform. Their molecules go from a random orientation to an ordered grid. Then, when the pressure is removed, they disturb again. As part of this disordering process, the crystals absorb heat, effectively cooling their surroundings.

Although pressure-based cooling like this has been studied before, most materials capable of making this transition can only do so at mild temperatures, limiting their cooling power, Pringle said. In contrast, her team's crystals exhibit their heat-absorbing ability at temperatures between -37°C (-34.6°F) and 10°C (50°F), a temperature suitable for home refrigerators and freezers. .

However, the new crystals are not yet ready to leave the lab. That's because the pressure required to make them work is so high, Pringle says, that it's hundreds of times greater than atmospheric pressure and equivalent to thousands of meters underwater.

david boldrin Researchers at the University of Glasgow in the UK said materials like the new study “have the potential to almost completely decarbonize this giant carbon”. [cooling] However, he shares concerns about the high pressure required.

He says there may be other practical problems with this approach. Bing Li At the Chinese Academy of Sciences. With each repeated use, the grid formed by the molecules becomes more distorted and each crystal absorbs less heat. Still, Lee said he was optimistic and believed the technology could be applied in the “near future.”