How can the power of moving water be harnessed to create usable energy?
I can think of 2 general ways:
- mechanical conversion
- heat differential
This would include traditional water wheel or turbine driven mills and electrical generators. Anything that could be used to cause the movement of some mechanical component (e.g. falling water or waves) could convert this motion into usable mechanical actions (e.g. flour or saw mills) or electrical current.
The temperature of (for example) falling water increases as it moves from the higher to the lower level. (This is why water at the bottom of a water falls is less likely to be frozen than water at the top during winter). Heat differential can be used to drive other mechanisms.