Theres a Dutch study indicating that we're rapidly approaching supply chain limits for the rare metals required for renewable energy, both solar and wind. I wonder how long renewables can continue dropping in price.
Solar, maybe, for now. But I can't imagine that there is a need for large amounts of exotic metals in a wind turbine, which is a simple generator. Exotic materials might give a percent or three more operational efficiency, but they're not actually necessary.
As far as I know neodymium is currently used for magnets in a lot of wind turbines and electric motors among other things. It's not rare but the vast majority of it comes from China right now. I can't speak to how much efficiency it adds.
Wind turbines are currently over 100 meters high and installed into places that see lot of wind. It's a rule of thumb that you should keep the natural frequency of any large steel building above 20 hz. Swiching to heavier magnets will increase the mass of the generator which is mounted on top. That in turn will make the whole thing more wobbly (ie lower the frequency). To combat this you need thicker frame. Which in turn will cost more and weight more.
It's completely possible that current windmill designs are only possible with neodymium magnets. We would need to ask turbine designer.
Actually, that makes a lot of sense. Neodymium magnets are much lighter and more compact for the same strength. (I know this from being a guitar player - exact composition of magnets in guitar pickups and speakers is a subject of substantial controversy, both technical and magical.)
But it also seems to me this might be a cost issue... it's possible that neodymium magnets are used because they're cheaper in context than ceramic, alnico, or other materials. That could change if neodymium prices increase substantially due to scarcity.
The mentioned study and information on components required for solar are very easy to search for if you're interested. I'm in no way against renewables but I wanted to highlight that it's early days for these technologies.
Let me be blunt: I was calling out a lie. Solar does not require rare materials, and you are either misrepresenting the study you are pointing to, or the study is mistaken. If this is the study I am thinking of, you're misrepresenting it.
Silicon PV (which is 95% of the market) uses no rare elements except silver for front contact wires, and that can be substituted for with copper if a diffusion barrier layer is added to prevent its reaction with silicon.
