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Comment by seec

1 day ago

Can you build an industrial plant to build the panels only using solar power?

How and from where do you source the necessary primary materials for such an endeavor?

If you try to answer those questions you will see that you are bullshiting yourself.

I have tried, actually. Maybe you can share what you've learned when you, hypothetically, investigated the question yourself. I'll start.

You do need materials, but you can source the materials anywhere on Earth; it's just a question of how expensive it is to refine them. Every element occurs as an impurity in every rock at some level. When you can import them freely, some deposits are uneconomic.

For building a plant to refine silicon, things like platinum and iridium, which are very scarce in most rocks, are very helpful. But they aren't ingredients in the solar cells themselves. Solar cells themselves are made of silicon, aluminum, silver†, lead, and tin, with trace quantities of phosphorus (or arsenic) and boron. These are mounted to "ultra-white" glass, which is made of silicon again, oxygen, sodium, calcium, and trace amounts of manganese. The mounting is done typically with EVA, which is mostly a hydrocarbon with a little oxygen in it.

The total amount of these materials is surprisingly small. The silicon wafer (2.33g/cc) is about 100μm thick, and the glass (2.5g/cc) is typically 2.5mm thick (3.2mm is "ultra thick"). So a square meter of solar panels, rated at some 200W, contains 6.3kg of glass (mostly oxygen and silicon) and 0.23kg of crystalline silicon, plus much smaller amounts of other materials.

So raw materials aren't a constraining factor unless you're living on a barge or a space station or something. Knowhow, organization, discipline, cooperation, etc., are the constraining factors. Sadly, those are in short supply almost everywhere.

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† Silver is used for large conductive strips on the surface of the silicon; it can be replaced with copper at a significant loss of efficiency. There is already pressure to do this because the raw-materials cost of silver accounted for about 10% of the wholesale cost of current PV modules last time I checked, and about 10% of global silver production went into PV modules. Since then production has increased and PV prices have dropped.