[crazy2be]

Yes, but aluminium smelting has certain constraints - namely, the molten metal cannot solidify[1]. This restricts your ability to quickly spin up and down smelters, but they are still potentially a very useful part of an energy smoothing strategy.

[1] https://en.wikipedia.org/wiki/Aluminium_smelting

[Baeocystin]

Sure. But the thermal mass of an in-use pot is significant, and that buys you time. You can read more about the details here:

http://www.aluminiumtoday.com/contentimages/features/Oyeweb....

It's a well-done summary, I think you'll find it interesting. The tl;dr is that power interruptions up to ~4-5 hours do not cause significant trouble.

[crazy2be]

Huh, interesting. I read the whole thing and understood at least half of it ;).

Are the damages primarily thermal? I couldn't figure it out from that report, although it seemed to somewhat hint that they were. I.e. if you could keep the cells warm (with more insulation or otherwise), would they still get damaged by the shutdown?