I just realised why all my power armors seemed to be at 0 charge when not being worn after a bit.
The belt immunity equipment is draining its 100kw constantly.
I tested with two sets of power armors, one with and one without belt immunity, charged fully and left in inventory for a bit. After a bit, the one with it had 0 charge, and the other was still full.
So this post is basically one of two, depending on your choise, devs.
Either this is a bug report, or a suggestion to have power generating items work when the armor is not worn
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