My neighbor did a similar system. He used 2 x 6 x 16 feet long and made a roof or frame on top of the container. Same as normal house framing. Used hurricane ties to attach the framing to the side of the container. So only holes in the side of the container. He also use the pond liner on the top of the container to keep water out. His frames were basically 2 x 6 lumber. He made it 16 feet wide so the container would have shading on the sides. You could do it that way or just put a vertical wall on yours. No, the containers just for storage. All the electrical equipment is somewhere else. If used for electrical equipment, I would certainly consider a refrigerated container since those are made to keep food frozen and they already come insulated. No need to mess with two by fours and fiberglass. Don’t have any batteries yet, but trying to figure out how to do this new non-export stuff. It’s a completely different world than net metering. The shipping container might be a good place to put batteries, though since they are flammable, we need to have something relatively fireproof. Of course, only the floor on a regular shipping container can burn. But again, if you get a refrigerated container that is completely non-flammable, including the floor. Only stainless steel and aluminum. And it’s insulated and will keep stuff cool. Most people never think about refrigerated containers, but if it’s a habitable place or you need to temperature control it I think it’s the only way to go. Normal shipping containers are great for storing items and keeping rodents and insects out but not for much else. Once you start having to insulate and do two by fours and sheet rock you might as well just buy the reefer to begin with. Cost will probably end up the same, but the reefer will be 10 times better.
It looks like you basically built an 'exoskeleton' of 2x4s around the structure? 
