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Regarding the greenhouse-gas emissions of air conditioners, it's more than just the induced demand for power generation (which in Egypt still depends heavily on

Regarding the greenhouse-gas emissions of air conditioners, it's more than just the induced demand for power generation (which in Egypt still depends heavily on fossil fuels [1]). I was a little bit surprised by that callout in the story, so I went looking for info on the refrigerants themselves. If you're old enough to remember the worries about the ozone hole over Antarctica, you might remember that we agreed to phase out CFCs as a refrigerant. They were replaced by HCFCs which are less dangerous to atmospheric ozone (yay) but have a very high impact as a greenhouse gas per unit mass (boo) [2]. Ultimately the HCFCs will be replaced with ammonia, propane, and other alternatives which have a lower greenhouse gas effect, on the same order of magnitude as CO2 [3]. [1] https://www.iea.org/countries/egypt https://www.iea.org/countries/egypt [2] https://unfccc.int/process/transparency-and-reporting/greenhouse-gas-data/greenhouse-gas-data-unfccc/global-warming-potentials https://unfccc.int/process/transparency-and-reporting/greenh... [3] https://climate.ec.europa.eu/eu-action/fluorinated-greenhouse-gases/climate-friendly-alternatives-hfcs_en https://climate.ec.europa.eu/eu-action/fluorinated-greenhous...

nocoiner 3y ago
I feel like the story was implied that refrigerants are consumed in the course of operation. I think that point could have been more artfully stated. Did you happen to notice whether HCFCs had worse greenhouse gas effects than CFCs?
- Full_Clark 3y ago
  That was the first impression I got from the story too. But I didn't think it was correct so that's why I went looking for clarification. The mechanism of release for refrigerants to the atmosphere seems to mainly be escape during servicing and decomissioning as well as microscopic leaks in aircon piping that develop over the working life of the unit. I haven't done the math on total amount of refrigerant emission to understand whether it's negligible in the big picture or actually a serious problem once CO2 emissions approach net zero. Is that why you're curious about HCFC vs CFC?
  - nocoiner 3y ago
    Yeah, I was just curious if we had traded one environmental catastrophe for another - like if HCFCs were better for ozone but far more potent greenhouse gas pollutants. I think I’ve read something along similar lines about another substance - perhaps how natural gas is actually a fairly clean burning fuel, but leakages of raw natural gas are terrible in terms of GHG potency.
    - Full_Clark 3y ago
      They're definitely potent but I don't know how the total emitted mass compares to CO2, or how their atmospheric lifespans affect the impact. I would bet the information is out there and has already been analyzed in IPCC reports or peer-reviewed studies. But the writing can be quite dense and I don't have time at the moment to do more than skim the documents that turn up in search. Given how they're constantly referred to as transition chemicals in reference to the banning of CFCs, I would expect that the warming potential of HCFCs is regarded as dangerous but necessary, and therefore a bad outcome but less bad than continued degradation of the ozone layer. FWIW, this document indicates that failing to abate the emission of methane, black carbon aerosols, ozone, and HFCs (note, a bigger class of gases than merely HCFCs) will result in an extra 0.5 degree C of warming by 2100. But I'm not sure what proportion of that belongs to each substance individually. https://pubmed.ncbi.nlm.nih.gov/15112799/ https://pubmed.ncbi.nlm.nih.gov/15112799/
  - fy20 3y ago
    I imagine cars are a much worse offender than AC in buildings due to the shorter lifetime and the harsher mechanical conditions. In my country during summer, at basically every large supermarket there are stands where you can have the AC refilled in your car.
    - Full_Clark 3y ago
      Interesting, I wouldn't have expected it to be a self-serve option. Not unless it's one of the refrigerants with much lower warming potential. If you're not comfortable sharing the specific country, which continent are you on?

nocoiner 3y ago

I feel like the story was implied that refrigerants are consumed in the course of operation. I think that point could have been more artfully stated. Did you happen to notice whether HCFCs had worse greenhouse gas effects than CFCs?

Full_Clark 3y ago
That was the first impression I got from the story too. But I didn't think it was correct so that's why I went looking for clarification. The mechanism of release for refrigerants to the atmosphere seems to mainly be escape during servicing and decomissioning as well as microscopic leaks in aircon piping that develop over the working life of the unit. I haven't done the math on total amount of refrigerant emission to understand whether it's negligible in the big picture or actually a serious problem once CO2 emissions approach net zero. Is that why you're curious about HCFC vs CFC?
- nocoiner 3y ago
  Yeah, I was just curious if we had traded one environmental catastrophe for another - like if HCFCs were better for ozone but far more potent greenhouse gas pollutants. I think I’ve read something along similar lines about another substance - perhaps how natural gas is actually a fairly clean burning fuel, but leakages of raw natural gas are terrible in terms of GHG potency.
  - Full_Clark 3y ago
    They're definitely potent but I don't know how the total emitted mass compares to CO2, or how their atmospheric lifespans affect the impact. I would bet the information is out there and has already been analyzed in IPCC reports or peer-reviewed studies. But the writing can be quite dense and I don't have time at the moment to do more than skim the documents that turn up in search. Given how they're constantly referred to as transition chemicals in reference to the banning of CFCs, I would expect that the warming potential of HCFCs is regarded as dangerous but necessary, and therefore a bad outcome but less bad than continued degradation of the ozone layer. FWIW, this document indicates that failing to abate the emission of methane, black carbon aerosols, ozone, and HFCs (note, a bigger class of gases than merely HCFCs) will result in an extra 0.5 degree C of warming by 2100. But I'm not sure what proportion of that belongs to each substance individually. https://pubmed.ncbi.nlm.nih.gov/15112799/ https://pubmed.ncbi.nlm.nih.gov/15112799/
- fy20 3y ago
  I imagine cars are a much worse offender than AC in buildings due to the shorter lifetime and the harsher mechanical conditions. In my country during summer, at basically every large supermarket there are stands where you can have the AC refilled in your car.
  - Full_Clark 3y ago
    Interesting, I wouldn't have expected it to be a self-serve option. Not unless it's one of the refrigerants with much lower warming potential. If you're not comfortable sharing the specific country, which continent are you on?