I believe we will see a dramatic increase in the next few years. The only external connection is water. Solar heat and natural ventilation are utilized for temperature and humidity control. It is like a protective shell sitting in a field providing season extension in the spring and fall. The basic system includes a metal frame covered with plastic, a trickle irrigation system, and a piece of black plastic on the ground, and roll-up sides.
More details follow.
Length is not critical, but width is. The width should not exceed the capacity for natural ventilation. In New England, a standard size is 14 x 96 feet. Size is partially dictated by the availability of various sizes of plastic. Framing materials include wood, PVC, and galvanized metal, the latter being the most popular and the most durable.