# Water cycle

The Sun evaporates water, rain refills rivers and lakes, and gravity brings it down again.

Source page: https://www.materialinsights.org/energy/e_hydro/

Natural sources · Solar-derived flows · No. 3

- Natural sources
- Origin: Indirect solar
- Renewable: Yes
 Natural sources · Solar-derived flows · Foundation · Energy

A cubic metre of water falling 100 metres holds only about 0.27 kWh, so hydropower has to move whole rivers.

Chart: Illustration: Water cycle

##### Where it comes from

Chart: Map of where it comes from

The Sun evaporates water, rain and snow drop it on high ground, and gravity pulls it back down through turbines, producing about 4,400-4,600 TWh in 2024.

##### Three things to know

1. Africa has harnessed only about 11% of its more than 600 GW of hydropower potential.
2. World hydro output fell about 5% in 2023 in drought, then rose about 10% in 2024.
3. Türkiye's hydro output dropped 14% over five years even though its capacity grew 15%.

##### The journey

1. 1 **Evaporation**Sunlight lifts water from seas and land
2. 2 **Rain and snow**Water falls on high ground
3. 3 **Rivers and reservoirs**Gravity gathers it into valleys and dams
4. 4 **Turbines**Falling water spins generators
5. 5 **Power and storage**Released on demand; 189 GW pumped storage
 Covered in [Earth's energy flows: sun, wind, water, heat and lifeEnergy](https://www.materialinsights.org/learn/energy/earths-energy-flows/)[Muscles, wood, water and wind: energy before fossil fuelsEnergy](https://www.materialinsights.org/learn/energy/energy-before-fossil-fuels/)

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/energy/e_hydro/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_hydro/correlation/index.md)
- [How energy resides](https://www.materialinsights.org/energy/e_hydro/resides/index.md)
- [Abundance](https://www.materialinsights.org/energy/e_hydro/abundance/index.md)
- [Fluctuation in time](https://www.materialinsights.org/energy/e_hydro/time/index.md)
- [Across the Earth](https://www.materialinsights.org/energy/e_hydro/geography/index.md)
- [Impact on nature](https://www.materialinsights.org/energy/e_hydro/nature/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_hydro/links/index.md)