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Big problem with aluminum is that it has less conductivity and thus is generating more heat in same diameter. However heat and air will cause aluminum cable to oxidize and as a result it will get

1) brittle to point of falling apart.

2) increases it's resistance through oxidation, which will increase heat

This is a big problem in Eastern Europe where communist were building concrete apartment towers wired with aluminum wires, it used to be major reason for fires before those towers were reconstructed and aluminum replaced by copper. Today it is forbidden to use aluminum wires in apartments and houses.

Aluminum is more-less unusable in installations where you can't shield it from air and where aluminum will heat up.




You can compensate for conductivity with larger diameters (modulo the skin effect, but there are options there too). At that point wires don't heat up so much and thus don't oxidize.


Also use higher voltages, and therefore lower currents.

Heat losses are proportional to the square of current, so relatively small voltage increases fix the problem.

> Aluminum is more-less unusable in installations where you can't shield it from air and where aluminum will heat up.

Your power was probably delivered over hundreds of km of uninsulated steel-cored aluminum wire.


So that's the reason why all aluminium wirings in buildings were ripped off and replaced with copper?


Ah! "Aluminum wire is unsuitable for use in enclosed, thermally unmanaged situations where it might have to carry sustained currents above specification. Especially where later addition of building insulation, long after wiring certification, might worsen heat removal."

Yes, true. Copper is better there. But it's irrelevant to wind turbines, EVs, BESSs, and power transmission.


Aluminum wiring is still useless, because slightest defect will cause it to oxide and fall apart, especially when you have smaller diameter, and that's the reason why it is not used and won't be used.

You can continue to live in your fantasy world, where aluminum is used widely, I am coming from there, we are ripping it from walls and replacing it with copper.


Aluminium wiring is still being used in buildings around the world. If the country where you're from banned aluminium wiring for some odd reason, it's probably that the wiring was defective and they couldn't legally or practically replace it with anything except copper wiring.


We used to use aluminum wirings for apartments/houses in Eastern Europe during communism because it was cheaper. It turned out that it does not work, it oxides, it will cause fires in buildings. Now it is outlawed.

Usage of aluminum in any small and high power electronics will cause exactly same issues for exactly same reasons


It is a matter of fact that aluminium wiring for appartements and houses is fine as long as the wires are correctly specified for the load. It works. There are plenty of houses with aluminium wiring that have stood the test of time and plenty more which will.

It's not rocket science. Aluminium is slightly less conductive so you have to make the diameter bigger (and coat it, etc...). When you do that, it is fine.

Aluminium can be and is used in smaller, high power applications, especially when weight is a concern, as it has a higher conductivity per unit mass than copper.

The issue with aluminium wiring in practice is not the aluminium oxidizing. Aluminium oxidisation is self limiting. It is an improper connection leading to a few nanometers of oxidation at the connection site, and thus higher temperature at the site of connection leading to a fire. This is avoidable but some places feel it is easier to ban aluminium wiring than enforce proper electrical connections.


With this logic we could be storing explosives at home, because everything is fine until they explode. Aluminum in house wirings is a ticking bomb, because you just need to make one mistake during connection and this will cause fire in few days, few months or few years.


It's not a ticking time bomb. If you make a grave mistake with bad connections, then it may be an issue. But this is true of all wiring. It's just that aluminium is more sensitive to bad connections.

As long as your electrician uses approved connections and does them to spec, there is no chance of a problem.


It is just wishful thinking that your electrician did not made a single mistake. Assume he did. Then what? You will burn to death at one random night?

Aluminum also expands and contracts much more than copper when it gets hot, so it can just wiggle its way out of any connection. Furthermore aluminum is soft, and if you bend it too much, it will crack or break, so not only connection can get problematic, any corners can get easily problematic as well.

Only madman would get his house installed with aluminum wiring.


Does skin effect even play a role in power delivery? We're not talking about high frequencies here, I suppose.


Yes, it does, at distances of thousands of km and 50 or 60 Hz. One of the reasons why high-voltage DC is preferred over those distances.




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