Your Waterwheel Solution
Hydro-Electric Potential in Kilowatts
The basic equation: kW = (( H * Q ) / 660 ) * 0.82 * 0.746 * (turbine / wheel eff.)
You will need to factor in the efficiency of the turbine or wheel that you are using to get a more realistic figure of your net potential.
kW == Kilowatts
H == Net Head in feet
Q == Quantity in Cubic Feet per Minute
660 == Constant
0.82 == Generator Efficiency
0.746 == Conversion from Brake horsepower to Kilowatts