Here are two i found, some of the panels are in place to divide the stalls, but not the fronts/gates yet. The tack room is pictured from the outside (inside the barn)
i did the same with panels for pens, each stall is10X8', i ended up with 8 stalls in a 30'X40' pole barn, with the one on the end with the door turned into a tack/feed room (enclosed with wood). i used 4' gates on each one. i was trying to find the photos but of course, since i'm looking, now...
Pretty sure heat lamps draw too much power to use with a solar set-up, however, i'm far from an expert. There are many posts on here and elsewhere advising against using heat for chickens in winter, they don't need it in general, and as long as your coop has adequate ventilation they should be...