Mark Kedzierski, a researcher at the National Institute of Standards and Technology (NIST), has developed a method to improve the energy efficiency of cooling systems in large commercial buildings. The principle is based on the addition of small quantities of lubricant in the coolant, this addition amplifying the heat transfers.
Mr. Kedzierski developed the guidelines for choosing the most suitable additive for the type of lubricant used in the cooling system. The optimum is reached when the lubricant complements the coolant in terms of surface tension and viscosity.
The lubricant then forms a film on the surface of the cooling liquid, which improves the efficiency of the transition to the gas phase. If this discovery is validated on a large-scale system, it would save about 1% of the 320 billion kWh used.
annually by cooling systems in the United States, equivalent to 5,5 million barrels of oil per year.