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Rare earth elements are not absolutely necessary for clean energy applications. They're generally cited as necessary for electric motors and turbines, but ther

Rare earth elements are not absolutely necessary for clean energy applications. They're generally cited as necessary for electric motors and turbines, but there are equally efficient work-arounds: https://eepower.com/news/eliminating-rare-earth-elements-in-electric-motors/ https://eepower.com/news/eliminating-rare-earth-elements-in-... > "Electric motors can also be made without using permanent magnets. An induction motor (also called a synchronous motor) operates on alternating current and uses electromagnetic fields produced by the stator (stationary) windings to induce a current in the rotor that produces an opposing magnetic field. By rotating the current around the stator windings, the rotor is induced to turn." Once that's eliminated (i.e. eliminating the need for strong permanent magnets), rare earths are only used in quite specialized applications: https://www.thoughtco.com/rare-earth-metals-2340169 https://www.thoughtco.com/rare-earth-metals-2340169

pfdietz 4y ago
Another potential substitute for permanent magnets is tetrataenite. https://en.wikipedia.org/wiki/Tetrataenite https://en.wikipedia.org/wiki/Tetrataenite It was recently discovered that FeNi relaxes to this phase much more quickly in the presence of ~1% phosphorus. https://pubmed.ncbi.nlm.nih.gov/36281692/ https://pubmed.ncbi.nlm.nih.gov/36281692/
- mikewarot 4y ago
  Also recently seen is the commercialization[1] of Fe16N2, which appears to have suitable characteristics as well. [1] https://www.nironmagnetics.com/ https://www.nironmagnetics.com/
- pencilguin 4y ago
  335 vs 512 for neodymium-iron-boron. Enough to be useful.
abakker 4y ago
This is true but also useless. AC synchronous motors cannot be easily substituted for Permanent Magnet DC motors in all use cases. BLDC motors with permanent magnets are drastically more energy dense and are easier to control. We've had AC Synchronous motors for a long time, but there is a reason that cordless drills have only been really good for a decade - BLDC motors. Likewise with drones, hoverboards, etc.
- baybal2 4y ago
elihu 4y ago
Induction motors tend to be quite a bit less efficient than permanent magnet motors though. Another option is to use permanent magnet motors that just don't use rare earth magnets. The Netgain Hyper9 (fairly commonly used in EV conversions) for instance doesn't use rare earth elements according to EVWest [1]. It's bulky and not particularly powerful, but it has pretty good efficiency. [1] https://www.evwest.com/catalog/product_info.php?products_id=469 https://www.evwest.com/catalog/product_info.php?products_id=... I believe some dual-motor EVs use a permanent magnet and an induction motor, the idea being that you can use just the permanent magnet motor most of the time for efficiency, but the induction motor is there for more power.

pfdietz 4y ago

Another potential substitute for permanent magnets is tetrataenite. https://en.wikipedia.org/wiki/Tetrataenite https://en.wikipedia.org/wiki/Tetrataenite It was recently discovered that FeNi relaxes to this phase much more quickly in the presence of ~1% phosphorus. https://pubmed.ncbi.nlm.nih.gov/36281692/ https://pubmed.ncbi.nlm.nih.gov/36281692/

mikewarot 4y ago
Also recently seen is the commercialization[1] of Fe16N2, which appears to have suitable characteristics as well. [1] https://www.nironmagnetics.com/ https://www.nironmagnetics.com/
pencilguin 4y ago
335 vs 512 for neodymium-iron-boron. Enough to be useful.

abakker 4y ago

This is true but also useless. AC synchronous motors cannot be easily substituted for Permanent Magnet DC motors in all use cases. BLDC motors with permanent magnets are drastically more energy dense and are easier to control. We've had AC Synchronous motors for a long time, but there is a reason that cordless drills have only been really good for a decade - BLDC motors. Likewise with drones, hoverboards, etc.

baybal2 4y ago

elihu 4y ago

Induction motors tend to be quite a bit less efficient than permanent magnet motors though. Another option is to use permanent magnet motors that just don't use rare earth magnets. The Netgain Hyper9 (fairly commonly used in EV conversions) for instance doesn't use rare earth elements according to EVWest [1]. It's bulky and not particularly powerful, but it has pretty good efficiency. [1] https://www.evwest.com/catalog/product_info.php?products_id=469 https://www.evwest.com/catalog/product_info.php?products_id=... I believe some dual-motor EVs use a permanent magnet and an induction motor, the idea being that you can use just the permanent magnet motor most of the time for efficiency, but the induction motor is there for more power.