• carbs@lemmy.world
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    3 days ago

    I’m not defending the article, but I think most overhead power lines are aluminium, which is probably good as it’s abundant compared to copper.

    • bluGill@fedia.io
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      3 days ago

      Aluminium is very commonly used. It isn’t near as good a conductor as copper, but you can easilly use more toeget results and in most cases that works fine.

      The reason we stopped using aluminimun more is it is relly tricky. when you tighten a screw the al deforms over time and so you don’t get a lasting connection. Al also corrodes to a non conductive state. Many house fires were traced to al wiring in just the few years it was common. We can mitigate all the above issuses but it takes care and so copper is preferred despite al being much cheaper.

    • Geodad@lemm.ee
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      3 days ago

      The problem with aluminum is that it gets REALLY hot when current is run through it. It used to be ised to wire homes, but is now banned because it wasn’t safe.

      • SomeoneSomewhere@lemmy.nz
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        3 days ago

        That’s incorrect. Aluminium is about 30% worse by volume than copper, meaning you need to go up a size. What stopped it being used for houses was that the terminations weren’t good enough, because aluminium has different thermal expansion and corrosion properties, plus they were using much worse alloys. That’s now mostly fixed and if you’re in the US, there’s a very good chance that your service main is aluminium, and there’s talk of allowing copper-clad aluminium (CCA) for subcircuit wiring.

        Per mass, aluminium is a better conductor, which is why it’s almost exclusively used overhead and in pretty significant volumes underground. The power grids were built on ACSR.