alt Hacker News> 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.
> 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.
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).