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Comment by revelation | Hacker News Reader

From what I've learned, silicon is abundant in the earth crust. The problem is that you need a very very high purity to make useful wafers. So technically, its not a problem of scarcity, just a lack of miners producing it in a very pure form, which could be solved by having more of them.

Are there some other difficulties that I'm overlooking?

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It's expensive to manufacture silicon at semiconductor quality, even when talking about polycrystalline wafers. (Monocrystalline wafers, used for "chips", is even more expensive and prone to defect." People are increasing production of polycrystalline silicon wafers but the demand is much greater than the supply, even with this increase. The cycle basically goes like this: polycrystalline gets more expensive because of demand -> supply increases -> prices go down (in theory) -> demand increases -> polycrystalline gets expensive again.

This is an endless loop right now, as the total amount of possible demand is >> than the growth of polycrystalline foundries. Furthermore, LCD displays also use this form of polycrystalline silicon, which doesn't help with the demand problem. Decently-graded silicon is inherently expensive to manufacture because of the process involved.

The takeaway is that if these metal-oxides are cheaper to produce, even if they are more expensive for the raw material, the cost savings would carry over to the products. Equally relevant when talking about solar cells is how much energy is needed to produce the cells themselves. Right now, an enormous amount of energy is required for silicon solar cells. Helping the energy crisis doesn't help if something takes that much energy to produce. (I do not know the ratio of lifetime energy output versus energy to manufacture but I am sure it's not very good.)

Again, you have this 180 degrees backwards. There was a huge rush to build out polysilicon module fabs in China that has caused a huge oversupply. Now module manufacturers are going out of business daily, leaving an oversupply of polysilicon capacity.

Here, from a few days ago:

http://www.pv-tech.org/news/polysilicon_headwinds_unchanged_...

That's really interesting. The industry is in a different place compared to when I was familiar with it.

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