Hydro cycle.

Like most of the other renewables, hydro-electric power is solar radiation as a result. The Sun starts the hydrologic cycle, water evaporating from the surface of the Earth that, subsequently, the precipitate and flowing over the surface of the land is able to provide this energy.

 

Bibliography:

Hyperlink: http://comunidad.eduambiental.org/file.php/1/curso/contenidos/docpdf/capitulo17.pdf
Photography:
1: Roxanne Raulovic adaptation
2.http://comunidad.eduambiental.org/file.php/1/curso/contenidos/docpdf/capitulo17.pdf