Run-of-river and small hydro: Overview

From village micro-hydro to waterwheels and pumps with no motor

What this tile covers Hydropower with little or no reservoir, from river plants to village micro-hydro. Share of use 0.2% share of world energy supply (2024)

Share of world total energy supply captured or extracted by each method, 2024 (latest year where noted). Denominator is the Energy Institute Statistical Review 2025 total of 592.2 EJ (physical energy content method); electricity from wind, solar, hydro and geothermal is counted at output, nuclear at reactor heat. Heat and biomass flows outside EI's total are set against the same 592.2 EJ. Small hydro (up to 10 MW) is about 79 GW, 6% of hydropower capacity (UNIDO); applying 6% to 16.03 EJ gives 0.96 EJ of 592.2 EJ (calculated). Assumes small plants run at the average hydro capacity factor. Source: World Small Hydropower Development Report 2022: English summary, UNIDO.

Key facts

Output

Electricity or motion

Included from the reference tables

Run-of-river plants
Small, mini and micro hydro
In-stream (hydrokinetic) turbines
Waterwheels and watermills
Hydraulic rams

Linked to the material world

H₂O Water

Also in Water and ocean

HyD Hydropower dams WEC Wave energy converters TdP Tidal and ocean-current power OTEC OTEC and salinity power

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