Installed Mac50 wheel
Toms low head electricity generating site in Ireland  
Smooth water entry makes use of the enire wheel width. The head has been raised slightly above axle height ... on ultra low sites like this every cm counts towards improved power output....
A deep settling basin makes a handy filter, taking out small stones, twigs and silt. Its part of the original drain system and not strictly necessary. The wheel is very tolerant of suspended materials.
Power take off at the axle transferred by chain speed up to the gearbox and induction generator. This produces 230 ac single phase straight from the machine for direct use, we can re-jig this for 3phase as well.    
The civils effectively hide half the wheel and its a characteristic of the midshot which runs in a cast 1/4 circle apron, not visible.
Overview of complete scheme, sleepers cover the outflow which rejoins a drainage channel. Power generation components are on the wall side where its cooler.
This stream fed system puts an unused sweetening flow to really good use. The water used to just fall uselessly into the adjoining drainage trench, now it drives a wheel to generate mains electricity and does it in a very compact space.
Systems like this are ideal where remote and reliable power is required ...  
Click images for larger pic
Water entry onto the wheel under power
Complete scheme overview
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