Fluorinated gases such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) make up the smallest percentage of GHGs but have high carbon-dioxide equivalence (CO2e) warming power. There are dozens of fluorinated compounds that contribute to global warming (if you’re interested, see page 211 of a pdf of the IPPC chapter here). Fluorinated gases’ CO2e (for 100-year timeline) range from as little as 59mt CO2e but many are in the thousands! Some of the higher CO2e include HFC-23 at 14,800mt CO2e, nitrogen trifluoride at 17,200mt CO2e, and sulfur hexafluoride at 22,800mt CO2e! Remember that this means that 1 mt of sulfur hexafluoride has the global warming potential of 22,800 mt of CO2. These compounds have a wide array of uses including high voltage electricity generation (sulfur hexafluoride), as refrigerants and in the manufacture of semiconductors (HFC-23), and the manufacture of flat panel displays and solar-energy cells (nitrogen trifluoride).
HFCs were introduced as a replacement for CFCs in refrigerants because CFCs were generating a growing hole in the ozone layer, letting in dangerous levels of ultraviolet (UVB) radiation. While HFCs don’t destroy the ozone layer, they contribute to global warming and climate change. Efforts to halt the production and use of HFCs has faced challenges. While a global agreement was reached (Kigali amendment to the Montreal Protocol) to phase out their production, emission levels have not declined as expected. As the Earth warms and nations develop, the growing demand for air conditioners contributes to the emissions of such refrigerants and electricity use… warming the planet further. See this NY Time story. At the current rate of growth, the number of air conditioners in the world is predicted to expand by 350% by 2050!