Tyson turbine

The Tyson Turbine is a hydropower system that extracts power from the flow of water, as opposed to the fall of water which powers most hydropower systems. It consists of a large propeller mounted below a raft, driving a power system,typically a generator, on top of the raft by belt or gear. The turbine is towed into the middle of a river or stream, where the flow is the fastest, and tied off to shore[?] to keep it there. It requires no local engineering, and can easily be moved to other locations.

External links:

Water Wheel Engineering (scroll down) (http://www.rosneath.com.au/ipc6/ch08/shannon/)