I vaguely remember watching a movie in my Kinder (1982-83) class about a couple of alien twins (a boy and a girl) who wear shiny silver jumpsuits- at some point they are caught by some type of authority and taken away in a white van in cages. Also, I think they had to "recharge" by having physical contact with each other- so since they're in cages away from each other they start dying. It's all pretty vague and it's totally possible that I am not remembering this accurately.
It takes place in the US, no idea where exactly though. :/
Any ideas? Please let me know if it sounds at all familiar.
Maybe one of the Witch Mountain movies? ESCAPE / RETURN TO WITCH MOUNTAIN?