When people talk about electronics and environmentalism, they tend to talk about planned obsolecence, rare earth metals, or pollution from manufacturing or recycling, which are all big problems of course, this is also something I’ve been wondering:
Most higher end electronics have metal casings made by CNC milling a solid piece of aluminum, magnesium alloy, or another metal. I think it was first made popular by Apple with their Macbooks. The first problem that I can think of is that a casing needs to be hollow, so you’re starting out with a solid piece of metal and carving it until most of it is gone, and even though the metal shavings can be recycled, both the CNC and the recycling process require energy, and the milling process also requires a constant stream of petroleum-based lubricant (though I’m not sure if you can just use something cleaner like water or if the oil can be reused).
Even if one uses electronics for as long as possible before upgrading (in which case most people want to future-proof by getting something higher end), do metal casings pose a sustainability problem? How does it compare to its main competitor, making casings out of plastic? Are there any other alternatives that are better than either? Maybe cast metal casings?
I guess the question in that case is if the energy required for recycled aluminum (which is starting to become more common thankfully) is outweighed by the effects of plastic, which includes microplastic contamination as you said, but also petroleum extraction and processing, which I’m not sure is better than aluminum mining.
Hemp plastic could be a solution though, and shows promise as structural plastic as opposed to just plastic bags and bottles. I wonder if the energy required is lower than recycled aluminum.