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Adding just the right dash of nanoparticles to standard mixes of lubricants and refrigerants could yield the equivalent of an energy-saving chill pill according to researchers at the US National Institute of Standards and Technology (NIST).

Experiments with varying concentrations of nanoparticle additives indicate they may well be able to improve the energy efficiency of large industrial, commercial, and institutional cooling systems known as chillers.

Specifically, NIST researcher Mark Kedzierski found that dispersing 'sufficient' amounts of copper oxide particles (30nm in diameter) in a common polyester lubricant and combining it with a refrigerant such as R134a improves heat transfer by between 50 per cent and 275 per cent.

But just how adding nanomaterials to lubricants improves the dynamics of heat transfer in refrigerant/lubricant mixtures is not thoroughly understood. And the process is far from foolproof. Kedzierski explained: 'In fact, an insufficient amount or the wrong type of particles might lead to degradation in performance.'