Refrigerant-12, the earliest refrigerant in auto a/c systems, was phased out of automobiles during 1991-94 in the U.S. because it depleted the ozone layer that protects us from skin cancer. The U.S. stopped making it in 1996. If you look at what’s called a global warming impact number that assigns one to CO2, then R-12 has a rating of 12,000.
Its replacement, R-134a has an index number of 1300. It cost the U.S. auto industry an estimated $8.5 billion to convert over, according to Ward Atkinson, the chair of the SAE Interior Climate Control Committee.
Now, R-134a could be on the way out—and SAE says that changeover could cost “significantly more.” The European Community signed the Kyoto Protocol, which lists R134a as a global warming gas. The EC is now in the process of phasing out R134a from 2011-2017 in favor of a refrigerant with an impact number of less than 150 – an order of magnitude down.
That move is trickling down to the U.S. California has proposed a ban of R-134a in trucks starting in 2015. One potential replacement refrigerant is R-152a, and a couple of other secret blends that are essentially unknown quantities regarding cost, material compatibility, performance and serviceability, including whether you can use it to service your R-134a system in the future. Automakers want a global replacement but there is not enough information, according to the SAE committee.
The U.S. Environmental Protection Agency (EPA) announced at SAE that it would sponsor a demonstration project to explore these areas. SAE experts and engineers from Delphi, General Motors, Ford, and Fiat are among the participants. However, time is short – contracts for new components need to be assigned by the end of this year.
Is there enough time for the industry to test and validate the new refrigerant and develop service procedures? No one knows for sure. Insiders are nervous. Improperly handled early customers of the new systems could provide the final development testing – and suffer the costs if reliability problems arise.--Ken Zino