My girlfriend's father farms in southern Sweden (near Växjö) and grows extensively in mobile greenhouses and uses them to house both his sheep in the winter, and his chickens. he has 6-10 of the same design.
Mobility: being in logging country, he mounts the each frame to two whole tree trunks running the length of the house. These serve both as weights (so it won't blow away) and as sledges, so he can drag the entire hoop house with his tractor.
Insulation: he uses Polypro greenhouse plastic lined with standard big bubble wrap, installed with the flat side towards the interior, this prevents both condensation from forming in the greenhouse (reducing solar gain) and provides insulation. With this method he can harvest his first crop of tomatoes at the end of March/early April, and his last in November. It never gets warm enough to be worth grow market veggies outside. the bubble wrap is also enough to insulate the sheep and chickens off their own body heat through long winter nights. The only (conventionally) heated structure on his farm is his house.