[Christ]

What's cool about that, is the entire assembly could essentially fit in a small air tank... so the vacuum chamber and the reinforced enclosure could be the same thing. The only thing from that point would be extracting said energy, and storing it to begin with.. while keeping the container under vacuum.

I'm pretty sure a Vacuum pump could pull enough air out of the assembly to create a vacuum, without it being completely sealed, but would it be worth the effort?

Also, with a Vacuum pump removing air from the assembly, and air coming in from other areas, would the airflow profile in the container create a negative effect on the bearings? i.e. wobbling, etc... since the bearings are obviously magnetic, and the flywheel would be floating.