Pump it up! In 45 litres of water raised by muscle power to a height of 4 metres, there is roughly enough energy to power a smartphone for 3 minutes – i.e. around 0.0005 kilowatt-hours (kWh). Let it rush!

The immense power of flowing water is harnessed to generate electricity with the aid of turbines – modern water wheels.

Reservoirs are important for hydropower generation. With pumped-up water, they can also provide a reliable means of energy storage: water can be released downhill at any time to drive the turbines of a hydropower plant. This ensures stable electricity supplies, even when solar or wind power dips.