Hydro
Hydropower Plant
A plant that converts the potential energy of stored or flowing water into electricity, including pumped-storage variants.
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Labelled system
Explore in 3D
Original ENERGY ATLAS schematic. Interactive 3D is opt-in on this page.
Creates head and controls flow.
Overview
Large hydro plants combine a dam or intake, waterways, a turbine, a generator, and a tailrace. Francis turbines suit medium heads; Kaplan machines suit low heads and high flow; Pelton wheels suit very high heads.
How it works
Water from a reservoir or river drops through a penstock. The turbine extracts energy. A generator converts torque to electricity. Pumped-storage plants reverse the flow using surplus electricity.
Components
Dam / intake
Creates head and controls flow.
Penstock
Pressurized conduit to the turbine.
Turbine-generator
Hydraulic machine coupled to an electrical generator.
Keep exploring
Articles
Hydropower
Falling or flowing water turns turbines. It is the oldest large-scale renewable electricity source still expanding in some regions.
8 min read
Francis, Kaplan, and Pelton Turbines
Three classic machines cover most hydraulic heads used in hydroelectric plants.
8 min read
Pumped-Storage Hydropower
Two reservoirs and a reversible plant make the largest form of grid electricity storage in many countries.
7 min read