This venture follows an earlier joint development agreement under which the two companies developed the product. The joint venture announced today is designed to provide DuPont and Honeywell with a source of supply to meet the growing demand faster than would be possible through either company’s individual efforts.

Current automotive air conditioners use hydrofluorocarbon HFC-134a, which has a GWP of 1430. The European Union’s Mobile Air Conditioning Directive requires that, starting in 2011, all new vehicle models use a refrigerant with a GWP below 150, and by 2017, all new automobiles sold in Europe will be required to use a low-GWP refrigerant. The new refrigerant, developed by DuPont and Honeywell, has a GWP of 4, which is 97% less GWP than the new regulation requires.

Prior to construction of a world-scale plant, the joint venture will begin supplying the refrigerant in the fourth quarter of 2011 in time to meet the European Union regulatory requirement.

Honeywell and DuPont introduced HFO-1234yf to the automotive industry in 2007, and since then, it has undergone extensive testing for safety and efficacy by independent testing groups such as the SAE International Cooperative Research Program, in which leading automakers participate. The SAE testing found the product offers environmental performance superior to carbon dioxide, an alternative refrigerant, while having “the lowest risk for use in mobile air conditioning systems in meeting environmental and consumer needs.”

However, the SAE publication Automotive Engineering reports that concerns have been raised over HFO-1234yf implementation that could, unless there are significant policy changes, limit HFO-1234yf application to OE installations, and perhaps fewer than anticipated. The issues were raised during a meeting of the SAE Interior Climate Control Committee at the SAE 2010 World Congress in Detroit. Among the concerns raised were:

• Cost. The refrigerant costs more to make and reportedly requires new plants, rather than conversion of a existing facilities. With the actual cost of producing HFO-1234yf unknown, the industry faces the problem of gaining acceptance for the refrigerant until production efficiencies and competition lower the cost closer to that of R-134a. The new Honeywell-DuPont JV will attempt to address some of those cost concerns.

• Patent issues.

• Integration of the new refrigerant into independent service shops.

The once clear-cut future to HFO-1234yf now is so murky that ICCC Chairman Ward Atkinson of Sun Test Engineering again raised the possibility of the secondary-loop system. In that, the refrigerant circuit is confined to under-hood, so a low-global-warming flammable refrigerant such as propane or the mildly flammable R-152a can be used in a protected environment. There it runs through a heat exchanger, chilling a liquid coolant, which then circulates through a passenger compartment (under-dash) heat exchanger.

HFO-1234yf is the preferred choice, even in Germany, where work on carbon dioxide (called R744 as a refrigerant) was mothballed to join what appeared to be a worldwide consensus. One quietly voiced hope: that we’re in a “lover’s spat” period, that agreements will come, including some R-134a taxation to reduce the price gap.

According to industry estimates, there are more than 400 million cars with air conditioning systems globally, with each system using between one half and one kilogram of refrigerant. Air conditioning systems using HFO-1234yf, developed by DuPont and Honeywell, are more energy efficient than carbon dioxide-based air conditioning systems, particularly at high ambient temperature conditions.

Resources

• Industry Evaluation of low global warming potential refrigerant HFO-1234yf (SAE, November 2009)