The free, renewable source of energy provided by falling water driven through turbines. Hydropower is the most important of the regenerable energy sources because of its highest efficiency at the energy conversion. There are two types of hydroelectric power plants: a) run-of-river power plants for the use of affluent water; b) storage power plants (power stations with reservoir) where the influx can be regulated with the help of a reservoir [...]. (Source: GEMET/PORT / PHC / PZ)