The Environmental Protection Agency on Feb. 28 gave a green light to an alternative automotive air conditioning refrigerant, hydrofluoroolefin-1234yf (HFO 1234yf). The compound in current widespread use, hydrofluorocarbon134a (HFC-134a), has a much higher global warming potential, the agency says.
Using a refrigerant with less global warming potential than HFC-134a is a cost-effective way for automakers to meet greenhouse gas emission standards for cars and light trucks that will take effect with model year 2012, EPA says.
With EPA's approval of HFO-1234yf, "the automobile industry now has the option to adopt a low global warming potential refrigerant that is also energy efficient, thus lowering the carbon footprint of every new automobile," says Terrence Hahn, a vice president for Honeywell, which produces the new compound in a joint venture with DuPont.
The chemical meets a European Union regulation that bans the use of HFC-134a starting this year and allows only refrigerants with a global warming potential of less than 150 (C&EN, July 26, 2010, page 23). HFO-1234yf has a global warming potential of four while HFC-134a is rated at 1,430.
HFO-1234yf was developed jointly by DuPont and Honeywell in response to the EU regulation, says a company spokeswoman. When DuPont commercializes the product later this year, the initial focus will be to supply automakers who are working to comply with the EU regulation, she tells C&EN. However, EPA's approval is another milestone in long-term commercialization, she says.