Clesson Brook, the stream I live beside, was an early 19th Century industrial zone. The Clesson drops about 800' in four miles, even in drought a couple cfs (in spate, could be a couple hundred cfs). It was overhead wheels every 5-10 m drop, NO MILL PONDS (not practical amount of storage in a very narrow valley, steep to the stream). A few were of course grist mills, but most of the wheels powered gang saws turning logs into boards or drop forges beating (iron) pigs into sheet iron. Our house was built for one of those millers.
Before turbines (and in this climate where it FREEZES) these few KW overshot wheels were ideal*. They were all they could handle. Shut down with a hand/body weight brake whenicing up threw them out of balance so could chip ice off. When reaction turbines were invented starting about 1830, industry moved to the larger rivers. BTW, my town(ship) not unique. Along the South River in the neighboring town of Conway a similar industrial zone.
You want/need millponds only when the flow is inadequate to power a "run of the river" plant and the terrain suitable. Even with turbines, say on the Deerfield River, there are currently seven hydro-electric plants but ONLY the one farthest upstream in Whitingham VT has a "mill pond" (a rather substantial man made lake).
* 16' drop and 4 cfs flow would produce ~4 KW if used by an overshot wheel << tangential flow impulse turbine tipped 90 degrees -- the impulse component negligible and not efficient but the fact that the out flow far lower than the inflow (gravity) was producing most of the power.-- so the impulse component usually neglected except by rules of thumb -- the wheel speed should be about half that of the initial drop onto the wheel and the buckets curved so when water flows out in the reverse direction to the rotation but peanuts
Another example where tilting can be used is the Poncelet Wheel. That looks like an "undershot wheel" but is also a tangential impulse turbine. Not very efficient, only about 60%. BUT if the frame of reference is rotated backwards about half the drop, and the wheel speed/diameter correctly chosen, efficiency goes up to about 80% (since half now coming from gravity)
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