Hydroelectricity is the term referring to electricity generated by hydropower, the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global electricity consumption, and 3,427 terawatt-hours of electricity production in 2010, which continues the rapid rate of increase experienced between 2003 and 2012.This book includes all key features related to plant setup,basic components of hydro plant and comparison of hydropower generation with other methodologies of electricity generation.Book also coverts some of the basi formulae related to hydro power generation.