Cool idea, though one challenge jumps to mind.
Not sure where you live, and you may be taking this into account already, but I don't see any insulation on the roofline. Looks like you have ductwork running through the room, but I didn't see any vents or means of climate control. The attics and crawlspaces of all the places I've lived have been hot as hell in the summer. I'd hate to poach the fish.