Refrigerants of the future

The high global warming potential of most HFC fluids is forcing a change to fluids with less environmental impact. The search for the ideal refrigerant is not new, but has been ongoing for one hundred years, even though the reason for the search has changed. The paper gives a background to the present search for new refrigerants, discusses the criteria for the selection and gives some information on the status concerning introduction of new fluids. In conclusion, there is only one new refrigerant close to be put on the market, HFO1234yf. Other closely related fluids, such as HFO1234ze may be alternatives in the future. Beside these new fluids, it is believed that natural refrigerants like hydrocarbons, ammonia and carbon dioxide, as well as the low GWP, but flammable, HFC152a, will all find a place in future refrigeration and heat pump systems.QC2012020