The goal was to make it out of the most affordable parts from any hardware store. This was made with 2 sheets of plywood, 11 2x4's, 2 PVC pipes, paint, skate bearings, bolts and screws and cost less than 200$ per unit without the generator (300$). The reason for the size was that the generator was 'high output' and could barely be turned by hand, if you choose to use a car alternator, then you should downsize this design and switch to metal flashing. I hope to have a link for files soon.
If you are in RENO, I recommend the drafting program for 3D AutoCAD. It will help you design and create whatever you like to build.