I am a graduate of electrical engineering and I have never thought of sustainable power supply this way before . I love the analysis you gave but I think this wiuld be limited to just a few persons who live by the river or stream .
You talked about the output being quite paltry but if this is incorporated with an inverter and a battery which you can use while charging, then I think you would be able to power your whole house comfortably. What do you think?
The output is actually better than most solar panel setups. The last one on the list outputs up to 1.6 kilowatts. Rooftop panels typically output no more than 250 watts each (under ideal conditions), and the cost of arrays with lots of panels adds up quickly.