Hydroelectric power - GaleHydroelectric power is electrical power derived from the energy in falling or moving water, a form of energy harvesting that makes hydroelectric power a potent alternative energy source. Hydroelectric power is a term applied to both the potential to do work as the result of the generation of electricity driven by falling or moving water and the overall system of generation itself. People refer to dams with electricity-producing turbines and generators as hydroelectric power plants, and the electricity generated (which is no different than electricity generated via wind or geothermal sources) as hydroelectric power.