Image: The GESPA group at IQS and the URV are working together on the STOP-F-GAS project, where they are studying, within the framework of the circular economy, the development of new technologies for absorbing fluorinated gases for their reuse and obtaining new, more sustainable refrigerant products. In the Kigali Amendment of 2016 to the Montreal Protocol, strict new deadlines were established to eliminate the use of various fluorinated gases. These gases – widely used in refrigeration systems, air conditioning and insulation, and other uses – have a very high global warming potential (GWP) that cannot be accepted within the current scenario of accelerated climate change the world is undergoing.
Katherine McMahonSarah Howard
A new study published in Environmental Science: Processes & Impacts affirms that moving away from the use of fluorinated gases (F-gases) for refrigeration – which contributes to global warming – is both possible and already happening in some sectors.
In short:
- Compared to F-gases, non-fluorinated gases are more efficient and do not break down into trifluoroacetic acid (TFA), a toxic byproduct of F-gases that’s harmful when inhaled.
- While switching to non-fluorinated gases may come with some trade-offs in initial costs and operating capacity, these are outweighed by improved environmental safety and reduced expenses over time.
Key quote:
“F-gases represented 2.5% of the total EU greenhouse-gas emissions in 2023 and reducing their direct emissions is an important element in efforts to limit global warming.”
Why this matters:
Despite their high global warming potential, F-gases are used in everything from fridges to air conditioners, heat pumps, dehumidifiers and dryers. Strong regulatory action has proven effective in eliminating ozone-depleting refrigerants in the past, but the substances that have replaced them – including F-gases – have their own dangers. The authors of this study emphasize that when searching for solutions to the issues caused by F-gases, any trade-offs on efficiency should be considered unacceptable due to the potential for environmental harm.
Related EHN coverage:
- Flaw in Montreal Protocol allows U.S. facilities to pollute
- Senate aims to redefine PFAS to protect key chemicals from regulation
More resources:
- Bangor Daily News:How to find home appliances that don’t emit ‘forever chemicals’, which shares guidance on shopping for appliances free of F-gases.
Glüge, Juliane et al. for Environmental Science: Processes & Impacts. Oct. 3, 2024
Finding non-fluorinated alternatives to fluorinated gases used as refrigerants†








Abstract
Hydrofluorocarbons (HFCs) and so-called hydrofluoroolefins (HFOs) are used as refrigerants in air conditioning, refrigeration, chillers, heat pumps and devices for dehumidification and drying. However, many HFCs, including R-134a and R-125, have a high global warming potential and some of the HFCs and HFOs degrade atmospherically and form trifluoroacetic acid (TFA) as a persistent degradation product. Rising levels of TFA around the globe reveal an urgent need to replace fluorinated refrigerants with non-fluorinated working fluids to avoid direct emissions due to leakage, incorrect loading or removal. It is important, however, also to select refrigerants with high efficiencies to avoid increasing indirect CO2 emissions due to higher energy consumption during the use phase. The present study investigates the available non-fluorinated alternatives to fluorinated refrigerants and shows that a transition to non-fluorinated refrigerants, in general, is possible and has happened in many sectors already. Technically, there are only slight barriers to overcome in order to replace fluorinated refrigerants in almost all newly developed systems conforming to existing standards. Additionally, we show that alternatives are available even for some use cases for which derogations have been proposed in the EU PFAS restriction proposal and suggest making these derogations more specific to support a speedy transition to non-fluorinated refrigerants in all sectors.
Environmental significance
Fluorinated gases that contain at least one fully fluorinated methyl (CF3–) or methylene (–CF2–) carbon atom are either persistent themselves or can form persistent degradation products. One of these degradation products is trifluoroacetic acid (TFA). Levels of TFA in the environment are increasing and will continue to increase if sources of TFA are not curbed. Replacing fluorinated gases with non-fluorinated alternatives is therefore of high importance as fluorinated gases are in terms of volume one of the largest group of precursors to TFA. Many of the fluorinated gases have also a lower efficiency than non-fluorinated gases when used as refrigerants, which leads to a higher CO2 footprint of refrigeration systems using those fluorinated gases.
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