Can hydroelectricity be used anywhere continued

We can find hydroelectric plants in 150 countries all over the world. China is the largest is the hydroelectricity producer. The power extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head. To build a dam the water has to have enough power and we also need slopes so the water comes with more power and we can produce more energy, that's why some countries can't use hydroelectric power. We can find it in those 150 countries because there is a lot of water everywhere and you can build dams nearly everywhere.

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