The Replacement For The Replacement Of The Original A/C Refrigerant In Cars May Itself Need A Replacement

Once considered a luxury, air conditioning is now standard equipment on pretty much every car sold in the U.S. today, but the refrigerant used in these systems has changed several times over the years.  Scientists discovered that what was originally promised to be a perfectly harmless compound wasn't really that harmless after all. And that cycle appears to be repeating yet again, as a recent study shows the relatively new R-1234yf is already contributing significant forever chemicals to the environment, reports Phys.org.

Air conditioning is great, and it's good for more than just cooling the air. Unfortunately, the refrigerants used in automotive applications of these systems have a long history of being environmentally unfriendly. The original compound, R12, worked quite well, but contained chlorofluorocarbons (CFCs) that contributed to holes in the ozone layer, according to the EPA. As a result, R-12 was banned in the 1990s and replaced with R-134a, a hydrofluorocarbon (HFC) that we were told would solve all the problems.

While R134a (also known as HFC-134a) does not poke holes in the ozone layer, it's turned out to be a major greenhouse gas. Automotive use of R-134a accounts for 24% of all HFC use and is the most common HFC currently in the atmosphere. Whoops. As is often the case these days, Europe, rather than the US, took the lead on addressing the problem of replacing the replacement. It phased out R-134a in 2017, and R-1234yf rose to take its place.

R-1234yf is a hydrofluoroolefin (HFO), rather than an HFC, that was supposed to address the shortcomings of both automotive refrigerants that came before it. It does not affect the ozone layer, and it is not a greenhouse gas. Problem solved, right?

Not so fast. A study by the University of Bristol has revealed that while R-1234yf (also known as HFO-1234yf) does provide these benefits, it is also becoming a major source of trifluoroacetic acid (TFA) in the atmosphere. According to ChemTrust, TFA is a "forever chemical" that can harm liver function and reproductive functions, including unborn children. R-134a has also been found to pollute TFAs, but not at nearly as high a rate as its replacement does. 

On a global scale, while R-134a emissions are about 22 times higher due to its long period of use since the 1990s, R-1234yf may already be generating three-quarters as many TFAs, despite only having been in use since 2017. Hotspots for current TFA emissions overlap parts of Europe with high vehicle emissions, where R-1234yf has seen greater use for a longer time than elsewhere in the world. It may be a sign of things to come.

Phys.org adds that while R-1234yf is not itself a greenhouse gas, it can break down into rather powerful greenhouse gases like carbon tetrafluoride, which has a global warming potential several times higher than R-134a, and HFC-23, which has an even stronger global warming potential than the old R-12 refrigerant. On top of all that, it costs more than three times as much as R-134a, contributing to the record-high prices of new cars. So it's more expensive, pollutes larger amounts of TFAs, and makes global warming worse than R-134a instead of better, like it was supposed to. Is it time to go back to what my mom called "4/40 air conditioning," which was four windows down and driving 40 mph? It would be a great excuse to bring back vent windows.