WEST LAFAYETTE, Ind. - Contractors who have mastered working with CFCs, HCFCs, and HFCs may now want to turn their attention to what is being promoted as the fourth generation of refrigerants - HFOs (Hydro-Fluoro-Olefins).

“We are on the verge of a new revolution in refrigerants,” said Denis Clodic of the Center for Energy and Processes at Ecole des Mines de Paris, during a plenary address before 500 engineers from 30 countries at the combined International Compressor Engineering and International Refrigeration/Air Conditioning conferences hosted by Purdue University.

He specifically cited research currently underway with HFO-1234yf that is being developed for mobile air conditioning, but may have applications in stationary equipment.

He noted that R-1234yf and the halogen-free natural refrigerant R-744 (CO2) are being studied closely because of lower global warming potential (GWP) than many HFC refrigerants. He called the research, “A new horizon for the development of refrigerants. Now GWP per se is a criterion for refrigerant choice” in Europe, he said.

Right now R-1234yf and R-744 are in competition, he said, to be the refrigerant of choice for automotive air conditioning in Europe, as governmental regulations are forcing auto manufacturers to move from HFC-134a because of global warming concerns about that refrigerant.

Clodic’s keynote talk came just before the scheduled presentation of a technical paper titled, “HFO-1234yf Low GWP Refrigerant Update,” by Barbara Minor of DuPont and Mark Spatz of Honeywell. Research teams from the two refrigerant manufacturers have been jointly working on the development of a refrigerant alternative for the automotive sector.

Minor and Spatz noted, “HFC-134a has been scheduled for phaseout in automobiles in the European Union beginning Jan. 1, 2011. HFO-1234yf has been identified as a new low global warming refrigerant, which has the potential to be a global sustainable solution for automotive air conditioning. R-1234yf is a pure compound which is highly energy efficient, exhibits low toxicity in testing to date, and can potentially be used in systems currently designed for R-134a with minimal modifications.”

The researchers went on to say, “Life Cycle Climate Performance (LCCP) calculations also indicate a significant environmental benefit versus R-134a, HFC-152a and CO2 in all major regions of the world. Though R-1234yf is mildly flammable per ASTM E-681-04 (ASTM, 2004), it is significantly less so than R-152 and HFC-32 and has the potential to be used in direct expansion systems without a secondary loop.”

Publication date: 08/11/2008