Strategic Energy Technologies Information System

European Initiative on Smart Cities

Hydropower: Technology Information Sheet


Hydropower electricity is the product of transforming potential energy stored in water in an elevated reservoir into the kinetic energy of the running water, then mechanical energy in a rotating turbine, and finally electrical energy in an alternator or generator. Hydropower is a mature renewable power generation technology that offers two desirable characteristics in modern electricity systems: first, built-in storage that enables electricity to be provided on demand and second, a fast response time that allows reserves to be fed into the grid.

Hydropower also has an important role to play in producing renewable electricity. It is low-cost and readily available: power flow is controlled through turbines to produce electricity on demand.