Quote:
Originally Posted by Hersbird
There are 2 different potential energies involved. The height is the main but there is energy in the velocity of water as well.
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I know what you mean, but height and velocity are the same "energies".
The height difference sets the velocity of water, either by the speed the stream flows (no dam), or by the pressure of the water at the turbine (dam).
All potential energy depends only the volume of water and the height differential.
The reason a dam is more efficient than turbines in a river is that more height differential can be harvested. Flow and power generation can also be modified as needed on a dam, whereas an open river delivers whatever the flow happens to be at the time.
Getting back to the thread title, it seems renewables are inevitable unless nuclear power really catches on.
As an aside, available renewable energy should be going up since the globe is warming. That means more wind, more rain, etc.