12 ms·

> "Rare-earths" are not, incidentally, needed for electric vehicles, wind turbines, or solar panels, however much certain people wish they were, or confidently

by culi 4y ago

> "Rare-earths" are not, incidentally, needed for electric vehicles, wind turbines, or solar panels, however much certain people wish they were, or confidently claim. What exactly does this mean? EVs use a ton more rare earth minerals than conventional cars https://www.iea.org/data-and-statistics/charts/minerals-used-in-electric-cars-compared-to-conventional-cars https://www.iea.org/data-and-statistics/charts/minerals-used... Solar panels use silicon, indium, gallium, selenium, cadmium, and tellurium. Neodymium and dysprosium are mainly used in the permanent magnets of offshore wind turbines

moloch-hai 4y ago
None of those used in solar panels are lanthanides. Current EVs use some lanthanides in magnets (soon to be displaced, as noted), but not in the batteries. Permanent magnets are used mainly in the smallest wind turbines, where offshore turbines are the biggest.
- culi 4y ago
  I see. I didn't realize "rare earth minerals" had a specific chemical definition
  - moloch-hai 4y ago
    "Rare-earth" means lanthanides plus scandium and yttrium. But scandium and yttrium are not used in magnets, so they would confuse people less by saying "lanthanide magnet" instead of "rare-earth magnet".
    - culi 4y ago
      There's actually 17 rare earth minerals. The Wikipedia page for it helpfully lists out common uses for each of them: https://en.wikipedia.org/wiki/Rare-earth_element https://en.wikipedia.org/wiki/Rare-earth_element
      - kragen 4y ago
        17 elements, but many more minerals in fact, almost all minerals contain trace amounts of rare-earth elements (and non-trace amounts are very rare)
      - moloch-hai 4y ago
        15 of the 17 "rare-earth" elements are lanthanides. The remaining scandium and yttrium are not lanthanides.
        culi 4y ago
        ah makes sense, thanks
  - a3w 4y ago
    It's just a name. They are not necessarily rare. It should be "certain transition metals", but transition is not what it seems in regard to "changing" in the common sense, either.
  - a3w 4y ago
    It's just a name. They are not necessarily rare. It should be "certain transition metals", but transition is not what it seems in regard to "changing" in the common sense, either. So, certain metals, it is.
  - a3w 4y ago
    It's just a name. They are not necessarily rare. It should be "certain transition metals", but transition is not what it seems in regard to "changing" in the common sense, either. So, certain metal ores, it is.
_ph_ 4y ago
The graph you linked shows that this is not true. See the tiny purple graph at the right side of the bar? That's the rare earth minerals and their amount in an electric car is tiny.
- moloch-hai 4y ago
  Right, says "0.5 kg 'rare-earths'" per vehicle. A biggish camera drone uses more.
  - aeyes 4y ago
    What is so special about a drone?
    - moloch-hai 4y ago
      Weight matters. They are all electric. They have electric motors made with permanent magnets.
- culi 4y ago
  Isn't 0.5kg per vehicle a lot for rare earth minerals?? Sure it looks tiny compared to the amount of copper, nickel, manganese, etc used, but the whole point is that they're rare... 0.5kg of neodymium is around $200 and it's probably the cheapest of the rare earths 0.5kg of europium is around $3,750 Obviously lots of variation there, but maybe ratio of how much it costs vs the total cost of all the other minerals is a better metric to use here than pure weight
  - kragen 4y ago
    ferrocerium is the cheapest of the rare earths, but if we're talking about purified elements, cerium and yttrium are probably cheaper than neodymium the reason the purified elements are expensive is that they're so hard to separate from each other rare earth elements aren't actually rare they're called that because we've inherited alchemical terminology from the 18th century when alchemists were first starting to discover that there were more than four elements, and that in particular there were several different kinds of earth, such as magnesia, silex, etc., and as it turns out things like thoria are in fact quite a bit rarer than silex
kragen 4y ago
most solar panels do not currently use indium, gallium, selenium, cadmium, or tellurium, none of which are rare earth elements (though indium is pretty rare) the solar panels that used those cannot economically compete with silicon pv for utility-scale solar any more (perhaps that will change) silicon is also not a rare earth element (and is not at all rare) evs and wind turbines can use rare earth elements, it's true, but it's just a relatively minor engineering tradeoff not to use them
- colechristensen 4y ago
  Silicon is perhaps the most available element on earth after nitrogen hydrogen and oxygen. Over a quarter of all rock by mass.
- initramfs 4y ago
  https://www.lowtechmagazine.com/2021/10/how-to-build-a-low-tech-solar-panel.html https://www.lowtechmagazine.com/2021/10/how-to-build-a-low-t... Schottky cells are another bandgap, which could be lower cost: "According to Philip Pesavento, Cove then managed to refine the composition of the alloy close to Zn4Sb3 – a zinc-antimony alloy with proportions of 4 parts zinc to 6 parts antimony. That, we now know, is also a semiconductor. However, it has a bandgap of 1.2 eV – very close to the bandgap of silicon (1.1 eV). Consequently, it turned his thermophotovoltaic generator into a photovoltaic generator: “In his enthusiasm, Cove probably made up a larger number of plugs and somehow got the proportions “wrong” on one batch. He then measured an even larger voltage. Finally, he made a careful study of zinc-antimony alloys and found that the 40-42% range zinc alloy gave the highest voltage (compared to 35% zinc in ZnSb). Having – accidentally – discovered Zn4Sb3, the higher bandgap of this semiconductor meant that it no longer worked when it was exposed to the heat from a wood stove. However, it worked even better when it was exposed to solar energy – because it was now converting far more of the visible spectrum of sunlight efficiently into electricity.” Using colored glass filters, George Cove determined that most of the response was from the violet end of the spectrum and only a little from the so-called heat rays. His earlier PV plugs had responded equally well to heat rays and violet rays, while the older thermoelectric generators (German silver at both sides) did not respond to the violet rays at all. Bring back the Schottky solar cell? Schottky junction solar cells have commanded only a small amount of attention from researchers and corporations – few solar cell designs use metals in the active region, other than for contacts. [22] Nevertheless, Philip Pesavento believes that it would be worthwhile to attempt to fabricate some Schottky solar cells according to Cove’s design: “If it could be demonstrated that Zn4Sb3 (bandgap 1.2 eV) can be used in a photovoltaic cell, there is a good chance that such a solar cell design will be sustainable. It would be a good candidate for a quick EROI and have an acceptably long operational life with a surplus energy output over several decades. It’s astounding that everyone seems to have missed this material and its application to photovoltaic cells and that no development has been done – even after researchers briefly recognized it as being a possible option in the early to mid-1980s. It fits in the category of a premature discovery which should mean it could be developed very quickly in this day and age.”

by culi 4y ago

moloch-hai 4y ago

None of those used in solar panels are lanthanides. Current EVs use some lanthanides in magnets (soon to be displaced, as noted), but not in the batteries. Permanent magnets are used mainly in the smallest wind turbines, where offshore turbines are the biggest.

culi 4y ago
I see. I didn't realize "rare earth minerals" had a specific chemical definition
- moloch-hai 4y ago
  "Rare-earth" means lanthanides plus scandium and yttrium. But scandium and yttrium are not used in magnets, so they would confuse people less by saying "lanthanide magnet" instead of "rare-earth magnet".
  - culi 4y ago
    There's actually 17 rare earth minerals. The Wikipedia page for it helpfully lists out common uses for each of them: https://en.wikipedia.org/wiki/Rare-earth_element https://en.wikipedia.org/wiki/Rare-earth_element
    - kragen 4y ago
      17 elements, but many more minerals in fact, almost all minerals contain trace amounts of rare-earth elements (and non-trace amounts are very rare)
    - moloch-hai 4y ago
      15 of the 17 "rare-earth" elements are lanthanides. The remaining scandium and yttrium are not lanthanides.
      - culi 4y ago
        ah makes sense, thanks
- a3w 4y ago
  It's just a name. They are not necessarily rare. It should be "certain transition metals", but transition is not what it seems in regard to "changing" in the common sense, either.
- a3w 4y ago
  It's just a name. They are not necessarily rare. It should be "certain transition metals", but transition is not what it seems in regard to "changing" in the common sense, either. So, certain metals, it is.
- a3w 4y ago
  It's just a name. They are not necessarily rare. It should be "certain transition metals", but transition is not what it seems in regard to "changing" in the common sense, either. So, certain metal ores, it is.

_ph_ 4y ago

The graph you linked shows that this is not true. See the tiny purple graph at the right side of the bar? That's the rare earth minerals and their amount in an electric car is tiny.

moloch-hai 4y ago
Right, says "0.5 kg 'rare-earths'" per vehicle. A biggish camera drone uses more.
- aeyes 4y ago
  What is so special about a drone?
  - moloch-hai 4y ago
    Weight matters. They are all electric. They have electric motors made with permanent magnets.
culi 4y ago
Isn't 0.5kg per vehicle a lot for rare earth minerals?? Sure it looks tiny compared to the amount of copper, nickel, manganese, etc used, but the whole point is that they're rare... 0.5kg of neodymium is around $200 and it's probably the cheapest of the rare earths 0.5kg of europium is around $3,750 Obviously lots of variation there, but maybe ratio of how much it costs vs the total cost of all the other minerals is a better metric to use here than pure weight
- kragen 4y ago
  ferrocerium is the cheapest of the rare earths, but if we're talking about purified elements, cerium and yttrium are probably cheaper than neodymium the reason the purified elements are expensive is that they're so hard to separate from each other rare earth elements aren't actually rare they're called that because we've inherited alchemical terminology from the 18th century when alchemists were first starting to discover that there were more than four elements, and that in particular there were several different kinds of earth, such as magnesia, silex, etc., and as it turns out things like thoria are in fact quite a bit rarer than silex

kragen 4y ago

most solar panels do not currently use indium, gallium, selenium, cadmium, or tellurium, none of which are rare earth elements (though indium is pretty rare) the solar panels that used those cannot economically compete with silicon pv for utility-scale solar any more (perhaps that will change) silicon is also not a rare earth element (and is not at all rare) evs and wind turbines can use rare earth elements, it's true, but it's just a relatively minor engineering tradeoff not to use them

colechristensen 4y ago
Silicon is perhaps the most available element on earth after nitrogen hydrogen and oxygen. Over a quarter of all rock by mass.
initramfs 4y ago
https://www.lowtechmagazine.com/2021/10/how-to-build-a-low-tech-solar-panel.html https://www.lowtechmagazine.com/2021/10/how-to-build-a-low-t... Schottky cells are another bandgap, which could be lower cost: "According to Philip Pesavento, Cove then managed to refine the composition of the alloy close to Zn4Sb3 – a zinc-antimony alloy with proportions of 4 parts zinc to 6 parts antimony. That, we now know, is also a semiconductor. However, it has a bandgap of 1.2 eV – very close to the bandgap of silicon (1.1 eV). Consequently, it turned his thermophotovoltaic generator into a photovoltaic generator: “In his enthusiasm, Cove probably made up a larger number of plugs and somehow got the proportions “wrong” on one batch. He then measured an even larger voltage. Finally, he made a careful study of zinc-antimony alloys and found that the 40-42% range zinc alloy gave the highest voltage (compared to 35% zinc in ZnSb). Having – accidentally – discovered Zn4Sb3, the higher bandgap of this semiconductor meant that it no longer worked when it was exposed to the heat from a wood stove. However, it worked even better when it was exposed to solar energy – because it was now converting far more of the visible spectrum of sunlight efficiently into electricity.” Using colored glass filters, George Cove determined that most of the response was from the violet end of the spectrum and only a little from the so-called heat rays. His earlier PV plugs had responded equally well to heat rays and violet rays, while the older thermoelectric generators (German silver at both sides) did not respond to the violet rays at all. Bring back the Schottky solar cell? Schottky junction solar cells have commanded only a small amount of attention from researchers and corporations – few solar cell designs use metals in the active region, other than for contacts. [22] Nevertheless, Philip Pesavento believes that it would be worthwhile to attempt to fabricate some Schottky solar cells according to Cove’s design: “If it could be demonstrated that Zn4Sb3 (bandgap 1.2 eV) can be used in a photovoltaic cell, there is a good chance that such a solar cell design will be sustainable. It would be a good candidate for a quick EROI and have an acceptably long operational life with a surplus energy output over several decades. It’s astounding that everyone seems to have missed this material and its application to photovoltaic cells and that no development has been done – even after researchers briefly recognized it as being a possible option in the early to mid-1980s. It fits in the category of a premature discovery which should mean it could be developed very quickly in this day and age.”