9 knots!! You are in business my friend. I was already designing this for the creek in my back yard, my easement only goes to the middle of it so no damming in my case either. My creek only flows about 6 mph. This thing is to be built on a budget so the blades or paddles are 1/3 sections of 6" PVC, the wheels are epoxy saturated exterior plywood, the center shaft is 1-1/2" galv. fence tube, bearings are probably going to be homemade from 1/2" nylon sheet. Otherpower style axial flux alt wound for 24V and bicycle provided chain and gear set. Floats are stacked 2" thick layers of white polystyrene foam hotwire cut to simple hull shapes under a 2x8 frame w/ 2x8 cross members. The foam displaces 125 lbs per cubic foot, so you can weigh your components as you build to figure how many cu. ft. of foam you need... Have fun, invite friends!
