When it rains dams fill up. The water is drained into shafts with turbines, and electricity is generated.
However, even though we are big on hydroelectricity percentage wise I’m not sure it’s all that vast an amount of electricity on a global scale. We are a pretty small country after all.
According to Wikipedia, the Norwegian electricity sector had 40.26 GW installed capacity as of 2021 and was producing 157.113 TWh in the same year. [1]
Great Britain had 74.8 GW installed capacity in 2023 and was producing 292.7 TWh in 2023. [2]
France was producing 537.7 TWh in 2020. [3]
Germany was producing 488.5 TWh in 2024. [4]
[1]: https://en.wikipedia.org/wiki/Electricity_sector_in_Norway
[2]: https://en.wikipedia.org/wiki/Electricity_in_Great_Britain
[3]: https://en.wikipedia.org/wiki/Electricity_sector_in_France
[4]: https://en.wikipedia.org/wiki/Electricity_sector_in_Germany