There is little differences in High Tunnels, hoop houses, poly-tunnels, and green houses. The biggest differences are if they are covered completely or partially in hard glass or plastic panels vs. a plastic sheet that comes on a roll, or if they have vertical walls for sides instead of the hoop extending into the ground, or if they are heated or have electric service in them. The ones I have here have solid end walls with a double layer of poly plastic sheeting over the rest. Ours also have four foot high walls that can roll up to increase ventilation in the summer and are heated by a wood burning furnace/boiler in the winter months. I can therefore raise a tropical fish like tilapia here in Kentucky during the winter months and keep the cycle of Aquaponics going year round. Our first HT is a 80×35 and is a “in ground” garden. The second one is a little smaller and houses the aquaponic system. The third has yet to be built but will be an off the grid operation using passive solar and rocket mass heating in the cold months and geo-thermal cooling in the summer months. Water and air pumps for the family sized off grid aquaponic and aeroponic systems will be 12 volt solar powered and operated, and with the option of bicycle, oxen or windmill power water pumps.