There are lots of generators/motors at conventional hydro power plants and pumped hydro storage systems that predate rare earth magnets. Weight is not an issue for them, so cheaper magnets are fine.
Interestingly, wind turbine companies are rapidly shifting away from rare earth magnets to electromagnets. Those are even lighter (and cheaper!) for a given field strength. Non-permanent magnets are a problem if you have to do a grid-wide black start -- see, eg, Spain/Portugal recently. I suspect that a battery installation big enough to jump start enough turbines to bring an entire farm back online has gotten quite cheap.
In 2024, an additional 38 GWh of grid-scale battery storage was deployed in the US. Almost all of that was lithium-ion. The biggest battery manufacturers look ready to start switching to sodium-ion for grid applications: it's safer, cheaper, uses less scarce materials, operates well over a wider temperature range, and the modest weight penalty doesn't matter.
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There are lots of generators/motors at conventional hydro power plants and pumped hydro storage systems that predate rare earth magnets. Weight is not an issue for them, so cheaper magnets are fine.
Interestingly, wind turbine companies are rapidly shifting away from rare earth magnets to electromagnets. Those are even lighter (and cheaper!) for a given field strength. Non-permanent magnets are a problem if you have to do a grid-wide black start -- see, eg, Spain/Portugal recently. I suspect that a battery installation big enough to jump start enough turbines to bring an entire farm back online has gotten quite cheap.
In 2024, an additional 38 GWh of grid-scale battery storage was deployed in the US. Almost all of that was lithium-ion. The biggest battery manufacturers look ready to start switching to sodium-ion for grid applications: it's safer, cheaper, uses less scarce materials, operates well over a wider temperature range, and the modest weight penalty doesn't matter.