Outlook for Natural Refrigerants ✓ Most Recent

The transition to low-GWP vapor compression systems presents technical challenges far more complex than the transition to zero ODP. Simply changing the refrigerant-lubricant mixture is not adequate; this transition requires redesign and optimization of all components because all affect the total equivalent warming impact. Compounding the challenges of maximizing COP are the difficulties of dealing with the toxicity, flammability or high-pressure characteristics of the candidate refrigerants - both natural and synthetic. The task of engineering around these characteristics complicated by inconsistencies and instability in the regulations aimed at minimizing those risks.

This paper builds on what is known about the performance of recently-developed prototype systems operating with natural refrigerants (CO2, hydrocarbons, NH3) and their low-GWP competitors, specifically R32 and fluorinated propene isomers of R1234. It also draws upon recent experience using demand-pull regulatory policies to move technologies along the learning curve in order to realize the economies of mass production. Finally it explores the various regulatory and economic forces that will be influencing the competition during the coming decades among low-GWP systems using natural or synthetic refrigerants, and assesses the outlook for natural refrigerants in each of the major market sectors.