How is a hydroelectric power plant dependent upon the sun?

Answer 1

Hydropower is dependent on the sun because the sun makes the water cycle work. The sun evaporates water in the ocean and from other places and then it rains into rivers which in turn flow into the Hydroelectric dams. If the sun wasn't there the water cycle would stop.

Answer 2

Hydroelectric power plants rely on the sun to drive the water cycle, as heat from the sun causes water to evaporate from oceans and form clouds. These clouds eventually release precipitation as rain or snow, which collects in rivers and streams that feed the hydroelectric plant's reservoir. The water stored in the reservoir is then released to flow through turbines, generating electricity.