The efforts are underway because HFCs are facing a phaseout for automotive air conditioning in European Union countries beginning in 2011. That phaseout does not affect automotive air conditioning in North America.

DuPont said that it has identified and is now testing proprietary refrigerants that the company said are expected to be compatible with conventional R-134a automotive air conditioning systems "with the potential for only minor modifications."

Honeywell said it has a patented developmental refrigerant "that can be used as a direct replacement for R-134a with minimal re-engineering of automotive systems."

The move away from HFCs in automotive air conditioning in Europe comes with questions about the global warming potential of HFCs. Both DuPont and Honeywell said their new non-HFC refrigerants respond to that issue. The Dupont statement said its refrigerants "have significantly lower GWP that current refrigerants." Honeywell said its new refrigerant is "a low GWP refrigerant."

When the phaseout of HFCs in European automotive was first announced several years ago, attention first turned to R-744 (CO2) as an alternative. But DuPont noted that the use of carbon dioxide "would require radical changes and the costly redesign of conventional automotive air conditioning systems," whereas the new refrigerants being developed would not require that. Honeywell said its refrigerant "is a more practical and cost-effective solution than CO2."

Publication date: 02/20/2006