alt Hacker NewsWith regards to the copper market: it keeps surprising me that some people seem to assume copper is a hard requirement for conducting electricity.
In reality copper is just convenient. We use it because it's easy to work with, a great conductor, and (until recently) quite affordable. But for most applications there's no reason we couldn't use something else!
For example, a 1.5mm2 copper conductor is 0.0134kg/m, which at current prices is $0.17 / meter. A 2.4mm2 aluminum conductor has the same resistance, weighs 0.0065kg/m, which at current prices is $0.0195 / meter!
Sure, aluminum is a pain to work with, but with a price premium like that there's a massive incentive to find a way to make it work.
Copper can't get too expensive simply due to power demands because people will just switch to aluminum. The power grid itself had been using it for decades, after all - some internal datacenter busbars should be doable as well.
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I am not an electricity/wiring guy so maybe you can help me understand. I thought aluminum is dangerous to wire with because it is a fire hazard (I bought a home this year and this was a prominent warning in my reading). Is that because it needs to be done very carefully? I imagine most data centers would not mess with a fire risk on such a scale.
Most residential 200A electrical panels use tin plated aluminum busbars. https://www.eaton.com/cr/en-us/catalog/power-connections/bus...
One good reason for moving from copper to aluminum is that copper contaminates recycled steel, but aluminum doesn't. Fortunately these days it's profitable to carefully extract most of the copper wire and such from scrap steel before it's melted down.
> In the Earth's crust, aluminium is the most abundant metallic element (8.23% by mass[68]) and the third most abundant of all elements (after oxygen and silicon).
TIL. I thought it would be relatively expensive due to the difficulty of extracting it.
(Iron is much cheaper than I thought, too.)
AFAIK Aluminum wires will become a heat liability, especially at higher amps
> In reality copper is just convenient. We use it because it's easy to work with, a great conductor, and (until recently) quite affordable
It's convenient, it's easy to work with, great conductivity, and cheap enough all at the sametime... Dude, I think you just explained why cropper is used instead of anything else.
> Sure, aluminum is a pain to work with
Really? In larger sizes, an equivalent ampacity aluminum cable is generally lighter and more flexible than copper. The main downside is that it’s thicker.
(Common terminations for larger wire sizes are often dual-rated for aluminum and copper. The engineering details for how to design lugs that work well for aluminum and copper were worked out long ago.)
interesting, thanks!
Aluminum conductors are dangerous unless the entire system is designed for it. It is not a case of switching to something cheaper.
Look at the electrical fires of the 1950’s and 1960’s as an example, and that was at household levels of current.
Aluminum is used, but everything accounts for the insane coefficient of linear expansion and other annoying properties.
You just have to not mix and match. If you mix them the two need special bonding at every single connector or they can cause arching and fires.