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Comment by hwillis | Hacker News Reader

> Solar modules contain lead for soldering

Not all of them, and lead is also non-essential. Most solder in other contexts is already lead-free. It's also pretty minor compared to the other sources of lead in our lives already.

> some contain cadmium telluride (CdTe)

only "thin film" cells, which are virtually obsolete- they're the flexible kind that you get in "cell charging" backpacks and stuff. Price decreases in silicon in large-scale use, so they have absolutely no bearing on renewable energy. They're not worth mentioning- a 100x increase in solar power will not increase the amount of cadmium cells at all.

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The reports I quoted in reply to another comment here claimed a rather high market share for CdTe cells and predicted massively increasing volumns in the future. So even if they might become obsolete for "classic" flat panels, they seem to remain with us for "flexible" solutions, arn't they?

The current global solar market is 170+ billion, compared to your reports giving CdTe <1 billion. That first link you posted estimates 60% annual growth, which seems... very not realistic.

https://www.fortunebusinessinsights.com/industry-reports/sol...

Lead solder is still preferred by many governments as its use is far safer for workers compared to lead-free solders. It's a constant fight between the manufacturing nations trying to protect their workers whereas the EU wants ROHS to make end-of-life recycling easier.

Why is lead-free solder less safe for workers?

The fluxes used with lead-free solder release about 2.5x as much particulate matter into the air and has been linked in multiple studies to a variety of lung issues. Current recommendations in the USA when working with lead-free solder is to do so in a downward pressure clean room of class 100,000 or better, in a fume hood, or while wearing an appropriate respirator while near the contaminated air. The flux used for leaded solder is a heavy particle that doesn't rise up as much when heated and can be handled safely with only fume extractors.

There's several other issues with lead-free solder that leaded solder does not have such as crystalline growths amongst a variety of other latent defects that can form well after cleaning and examination is completed.

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