• Duamerthrax@lemmy.world
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    13 days ago

    Just a reminder that concrete releases huge amounts of CO2 as it cures. Empty cities don’t help anyone.

    • grue@lemmy.worldBanned from community
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      13 days ago

      Another reason good urbanism and walkability is super important: the emissions don’t just come from the cars, they come from the excess roads themselves, too.

      • AA5B@lemmy.world
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        12 days ago

        It wasn’t even necessarily a bad idea given property growth, but it will be interesting to see what happens if they can’t stop population decline

      • Duamerthrax@lemmy.world
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        12 days ago

        Their intention was to bolster the economy with busy work, but that’s not a long term solution.

          • Duamerthrax@lemmy.world
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            12 days ago

            That’s comparing Apples to Shampoo. To completely different concepts and it’s not an either/or situation.

              • Duamerthrax@lemmy.world
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                12 days ago

                Concrete doesn’t house CO2. When they created Biodome2, the engineers didn’t factor in the curing time and CO2 output and the scientists had to vent the facility or suffocate.

          • Bytemeister@lemmy.world
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            12 days ago

            Houses don’t stand long on their own. It takes a significant amount of time and money to keep these things from filling up with mold or collapsing.

    • gandalf_der_12te@discuss.tchncs.de
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      12 days ago

      cement releases large amounts of CO2 when it is being produced, i.e. when the cement powder is being produced from limestone. this is due to a chemical reaction: CaCO3 (limestone) -> CaO (cement) + CO2

      later, when you mix the cement with water and sand to make concrete, it re-absorbs (approx. 43% of) that CO2. you’ve got it backwards :D

      curing reaction: CaO + CO2 -> CaCO3 (facilitated by water presence)


      edit: ok i looked it up and concrete only absorbs about 43% of the CO2 that is emitted during cement production. Source