Hydropower

Hydropower is a form of renewable energy that generates electricity by using the energy of flowing or falling water. It is one of the oldest and most widely used renewable energy sources in the world.

How hydropower works

1. Water is stored in a reservoir behind a dam (or flows naturally in a river).
2. The water moves through turbines.
3. The flowing water spins the turbines.
4. The turbines drive generators that produce electricity.
5. Electricity is transmitted through power lines to homes and businesses.

Types of hydropower

• Impoundment facilities: Use dams and reservoirs to store water.
• Run-of-river systems: Generate electricity from natural river flow with little or no storage.
• Pumped-storage hydropower: Stores energy by pumping water uphill when electricity demand is low and releasing it when demand is high.

Advantages

• Renewable and low-carbon energy source.
• Reliable and capable of producing large amounts of electricity.
• Can respond quickly to changes in electricity demand.
• Long operating life and relatively low operating costs.

Disadvantages

• High initial construction costs.
• Can affect river ecosystems and fish migration.
• Reservoirs may displace communities and alter landscapes.
• Electricity generation can be affected by droughts and changing rainfall patterns.

Global importance

Hydropower supplies a significant share of the world’s renewable electricity and is especially important in countries such as China, Brazil, Canada, and Norway.

If you’d like, I can also explain:

• the physics behind hydropower,
• the environmental impacts,
• famous hydroelectric dams around the world, or
• how hydropower compares with solar and wind energy.