The primary natural resource used to generate electricity in hydroelectric dams is water. Hydroelectric power relies on the kinetic energy of flowing or falling water to spin turbines, which convert it into electrical energy. Dams are built to create reservoirs that store water, and when water is released, it flows through turbines at the dam, generating electricity. This renewable energy source is favored for its low emissions and ability to provide consistent power. However, the construction of dams can have ecological and environmental impacts, including altering water ecosystems and displacing communities, necessitating careful planning and management.