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by cesarb 173 days ago
> Any electricity produced by turning generators will require rare earths.

AFAIK, not all kinds of rotating generators require rare earths; IIRC, induction motors don't need any permanent magnets.

1 comments

AFAIK, modern wind turbines use types of induction motors because it allows them to adjust the rotation speed by applying a counter-rotating stator field (which is a very neat trick) - older turbines had to rotate at a fixed divisor of 3600 rpm (grid frequency).