Hydropower is the generation of power by obstructing the flow of rivers, streams or other water sources and using its kinetic energy to power a turbine, which can generate decentralized power for communities. While hydro is a steady, low-impact form of power and systems can last for decades, it is dependent on the availability of a strong, steady flow of water. Therefore, it is used most often in regions with mountain streams such as Peru and Nepal. Plants are generally large enough to be most functional at a community level, rather than household level.