Not-in-Kind Alternatives to High Global Warming HFCs

As parties to the Montreal Protocol consider an amendment to phase down hydrofluorocarbons (HFCs), one critical concern is the availability of zero- or low-global warming potential (low-GWP) alternatives to replace high-global warming potential (GWP) HFCs. While much of the attention has focused on the next generation of fluorocarbons (hydrofluoroolefins—HFOs), not-in-kind (NIK) alternatives1 have in the past, and are likely to continue in the future, to play an important role in phasing down substances controlled under the Montreal Protocol. While no definitive estimate exists, according to one report, NIK alternatives, recycling and emission reductions historically replaced up to 85 percent of ozone-depleting substances.2 While the future role of NIKs may be more limited, these solutions, along with lower-GWP HFCs, are likely to continue to play an important role in expanding the range of substitute options while also providing market competition for new fluorocarbon chemical alternatives, which may be restricted in the near term by patents.