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I don't know what they are writing about. PV wafer reclaim has been around for at least a decade, at least in China. Reclaiming a cell is as easy as polishing

I don't know what they are writing about. PV wafer reclaim has been around for at least a decade, at least in China. Reclaiming a cell is as easy as polishing off its surface layer, which contains most of defects, and resurfacing it. A much more crude method just heats up the cell to the temperature where most defects from solar radiation disappear, but not hot enough for dopants to start diffusing more than they should, and then reselling it as a lower spec cell.

casefields 6y ago
California Department of Toxic Substances Control: https://dtsc.ca.gov/solarpanels/ https://dtsc.ca.gov/solarpanels/
- yorwba 6y ago
  > Q: How are solar panels hazardous? > A: Solar panel wastes include heavy metals such as silver, copper, lead, arsenic, cadmium, selenium that at certain levels may be classified as hazardous wastes. > Q: What does data show? What are the constituents that make the panels hazardous? > A: In general, data shows that older silicon panels may be hazardous due to lead solder. Some older silicon panels are hazardous for hexavalent chromium coatings. Cadmium tellurium (CdTe) panels are typically hazardous due to the cadmium. Gallium arsenide (GaAs) panels may be hazardous due to the arsenic. Thin film panels, such as copper indium gallium selenide (CIS/CIGS) panels, may be hazardous due to the copper and/or selenium. > Q: What about electronic components associated with the solar panels? What are they hazardous for? > A: The electronic components associated with the solar panels (e.g. drivers, inverters, circuit boards) contain all of the common electronic device hazardous constituents such as lead, arsenic, cadmium, selenium, and chromium.
  - hwillis 6y ago
    > A: Solar panel wastes include heavy metals such as silver, copper, lead, arsenic, cadmium, selenium that at certain levels may be classified as hazardous wastes. Note that this is grouping together ALL kinds of cells, particularly cadmium telluride. These cells -especially gallium-based cells- are a small or tiny minority of solar panels. The vast majority of solar panels do not contain any of these except copper and lead. Lead is actively in the process of removal, but the plan is to do so over the next decade or so. Regardless roughly 2000x more lead is used to make car batteries: https://www.freeingenergy.com/are-solar-panels-really-full-of-toxic-materials-like-cadmium-and-lead/ https://www.freeingenergy.com/are-solar-panels-really-full-o...
    - WWLink 6y ago
      Naw bro, we should just give up on the whole thing and go back to beautiful clean coal! lol jk.
- hamandcheese 6y ago
  “This product is known to the state of California to cause cancer.”
  - ben_w 6y ago
    Are there even any substances known to the state of California to not cause cancer? Air, salt, and all sugars fats and alcohols from things which consume air, are a bit radioactive.
    - dzhiurgis 6y ago
      Cannabis
      - ben_w 6y ago
        Carbon 14 from the air, so no.
kube-system 6y ago
Can mechanically damaged cells be reclaimed, and/or is the scrap value of cells high enough to encourage them to be removed gently?
- baybal2 6y ago
  Mechanically damaged cell cannot be reclaimed. Cut, or non standard sized cells are likely to be going into smelter too.
- pjc50 6y ago
  You could just chuck them back in the furnace, I suppose: https://en.wikipedia.org/wiki/Czochralski_method https://en.wikipedia.org/wiki/Czochralski_method .. but that's no better than using sand.
  - baybal2 6y ago
    Not so fast, silicon that was already doped cannot be reused for semiconductor manufacturing. It mostly goes to metallurgy.
biophysboy 6y ago
Your comment made me wonder something: how delicate are solar panels? Like, if a hailstorm hits a town with solar panels, will they be completely destroyed?
- noscrewstoyous 6y ago
  they will not (have panels, faced multiple hail storms)
- kube-system 6y ago
  The cells themselves are very delicate, much of the job of the panel is to protect the cells. Construction can vary, but generally they are designed to withstand normal weather events, just like a roof is. That said, weather can occasionally exceed those design limitations. Large hail can break through a polycarbonate skylight or the tempered glass of a car, it’ll do the same to a solar panel covered in the same.
- dapids 6y ago
  You know, that would be a very serious design flaw of they just broke like that. Hence the reason they are weatherproof... The solar cells themselves are usually quite delicate, but the surrounding material keeps them safe in the case of weatherproof ones.
  - biophysboy 6y ago
    I thought that as well, but then I thought "well car windshields can be busted by hail, so maybe there is just insurance, like we have for cars". By the replies I've gotten, looks like that's not the case!
- johnconnolly 6y ago
  From a solar installer in Colorado: https://blog.namastesolar.com/hail-solar-panels-how-much-hail-can-solar-panels-handle https://blog.namastesolar.com/hail-solar-panels-how-much-hai.... seems they're likely damaged by hail roughly the size of a golf ball, but in the link above they point to an example where 2.75in diameter hail did little damage to panels at NREL.
deleted 6y ago
[deleted]
baybal2 6y ago
P.S the company that recycles mono-si cells: http://www.wurisolar.com/ http://www.wurisolar.com/
pfdietz 6y ago
The obvious use to recycle silicon cells is to replace metallurgical silicon (which is far less pure) in the feed to the production of trichlorosilane. Failing that, just melt it with aluminum in the production of silicon-aluminum alloys.

casefields 6y ago

California Department of Toxic Substances Control: https://dtsc.ca.gov/solarpanels/ https://dtsc.ca.gov/solarpanels/

yorwba 6y ago
> Q: How are solar panels hazardous? > A: Solar panel wastes include heavy metals such as silver, copper, lead, arsenic, cadmium, selenium that at certain levels may be classified as hazardous wastes. > Q: What does data show? What are the constituents that make the panels hazardous? > A: In general, data shows that older silicon panels may be hazardous due to lead solder. Some older silicon panels are hazardous for hexavalent chromium coatings. Cadmium tellurium (CdTe) panels are typically hazardous due to the cadmium. Gallium arsenide (GaAs) panels may be hazardous due to the arsenic. Thin film panels, such as copper indium gallium selenide (CIS/CIGS) panels, may be hazardous due to the copper and/or selenium. > Q: What about electronic components associated with the solar panels? What are they hazardous for? > A: The electronic components associated with the solar panels (e.g. drivers, inverters, circuit boards) contain all of the common electronic device hazardous constituents such as lead, arsenic, cadmium, selenium, and chromium.
- hwillis 6y ago
  > A: Solar panel wastes include heavy metals such as silver, copper, lead, arsenic, cadmium, selenium that at certain levels may be classified as hazardous wastes. Note that this is grouping together ALL kinds of cells, particularly cadmium telluride. These cells -especially gallium-based cells- are a small or tiny minority of solar panels. The vast majority of solar panels do not contain any of these except copper and lead. Lead is actively in the process of removal, but the plan is to do so over the next decade or so. Regardless roughly 2000x more lead is used to make car batteries: https://www.freeingenergy.com/are-solar-panels-really-full-of-toxic-materials-like-cadmium-and-lead/ https://www.freeingenergy.com/are-solar-panels-really-full-o...
  - WWLink 6y ago
    Naw bro, we should just give up on the whole thing and go back to beautiful clean coal! lol jk.
hamandcheese 6y ago
“This product is known to the state of California to cause cancer.”
- ben_w 6y ago
  Are there even any substances known to the state of California to not cause cancer? Air, salt, and all sugars fats and alcohols from things which consume air, are a bit radioactive.
  - dzhiurgis 6y ago
    Cannabis
    - ben_w 6y ago
      Carbon 14 from the air, so no.

kube-system 6y ago

Can mechanically damaged cells be reclaimed, and/or is the scrap value of cells high enough to encourage them to be removed gently?

baybal2 6y ago
Mechanically damaged cell cannot be reclaimed. Cut, or non standard sized cells are likely to be going into smelter too.
pjc50 6y ago
You could just chuck them back in the furnace, I suppose: https://en.wikipedia.org/wiki/Czochralski_method https://en.wikipedia.org/wiki/Czochralski_method .. but that's no better than using sand.
- baybal2 6y ago
  Not so fast, silicon that was already doped cannot be reused for semiconductor manufacturing. It mostly goes to metallurgy.

biophysboy 6y ago

Your comment made me wonder something: how delicate are solar panels? Like, if a hailstorm hits a town with solar panels, will they be completely destroyed?

noscrewstoyous 6y ago
they will not (have panels, faced multiple hail storms)
kube-system 6y ago
The cells themselves are very delicate, much of the job of the panel is to protect the cells. Construction can vary, but generally they are designed to withstand normal weather events, just like a roof is. That said, weather can occasionally exceed those design limitations. Large hail can break through a polycarbonate skylight or the tempered glass of a car, it’ll do the same to a solar panel covered in the same.
dapids 6y ago
You know, that would be a very serious design flaw of they just broke like that. Hence the reason they are weatherproof... The solar cells themselves are usually quite delicate, but the surrounding material keeps them safe in the case of weatherproof ones.
- biophysboy 6y ago
  I thought that as well, but then I thought "well car windshields can be busted by hail, so maybe there is just insurance, like we have for cars". By the replies I've gotten, looks like that's not the case!
johnconnolly 6y ago
From a solar installer in Colorado: https://blog.namastesolar.com/hail-solar-panels-how-much-hail-can-solar-panels-handle https://blog.namastesolar.com/hail-solar-panels-how-much-hai.... seems they're likely damaged by hail roughly the size of a golf ball, but in the link above they point to an example where 2.75in diameter hail did little damage to panels at NREL.

deleted 6y ago

[deleted]

baybal2 6y ago

P.S the company that recycles mono-si cells: http://www.wurisolar.com/ http://www.wurisolar.com/

pfdietz 6y ago

The obvious use to recycle silicon cells is to replace metallurgical silicon (which is far less pure) in the feed to the production of trichlorosilane. Failing that, just melt it with aluminum in the production of silicon-aluminum alloys.