The most eminently practical and cost effective design I've come across is the T32 as designed by Dave Zeiger of Alaska. I've rendered a 10' wide one (T32x10) in these pictures. Constructing the vessel will likely be the easy part of this project. The harder part is building the network and solving the various logistical puzzles to ensure a smooth launch of the model. Not to mention the software components I have in mind for the sales platform, which are rather out of this farmer's depth. Various plans to build it next year are under discussion, including building it at my farm and also possibly at a school. The beauty of this design is that it can be transported on a mobile home trailer quite easily and thus stored on the farm inexpensively when not in use.