Besides what others have said, they'd know the capabilities of the address when it's built, at a minimum, as they're responsible for providing the infrastructure to deliver power to it.

I really don't get why you're asking this - they need to know what a facility is capable of to manage and plan power delivery.

As an aside, graphs like this are wildly wrong. Mine says the comparison is made between residences from 0.5 to 1.5 times the size of mine, within a 7 mile radius. So it includes apartments downtown who's heat is steam, and each unit insulates each other, and the building has a dozen to 100 bodies in it, heating it up.

That makes for a completly irrelevant comparison.