Researchers from the UK and
Spain have identified an eco-friendly solid that could replace the inefficient
and polluting gases used in most refrigerators and air conditioners. When
put under pressure, plastic crystals of neopentylglycol (NPG) yield huge
cooling effects - enough that they are competitive with conventional coolants.
NPG is widely used in the synthesis of paints, polyesters, plasticisers and
lubricants. NPG's molecules, composed of carbon, hydrogen and oxygen, are
nearly spherical and interact with each other only weakly. Due to the nature of
their chemical bonds, organic materials are easier to compress. In addition, the
material is inexpensive, widely available and functions at close to room
temperature. Details are published in the journal Nature
Communications. The gases currently used in the vast majority of
refrigerators and air conditioners - hydrofluorocarbons and hydrocarbons (HFCs
and HCs) - are toxic and flammable. When they leak into the air, they also
contribute to global warming.