The water behind a hydroelectric dam stores gravitational potential energy since it is at a higher level than the water on the other side of the dam. As the water falls, this potential energy is converted into kinetic energy, which turns turbines to generate electricity. Often, the water comes from behind a dam built across a river valley. The water high up behind the dam contains gravitational potential energy . This is transferred to kinetic energy as the water rushes down through tubes inside the dam. The moving water drives electrical generators , which may be built inside the dam.
