Old shipping containers

A question from a fellow grower:

I was wondering do you know anything about growing in old shipping containers that were refrigerators, in cold climates, that are off the grid and 40ft in length 10ft high? I was wondering about best way to heat and to warm the makeup air, how much air circulation is needed or is keeping it sealed and running co2 better?

I would keep it sealed if heating is an issue you live in cold climate but even then it requires some control so mixing small amount of fresh outside air and venting air with a temp controlled damper is an option