ABSTRACT
Hydroelectric power generation involves the storage of a hydraulic fluid, water, conversion of the hydraulic energy of the fluid into mechanical energy in a hydraulic turbine, and conversion of the mechanical energy to electrical energy in an electric generator. Hydroelectric plants are located in geographic areas where they will make economic use of hydraulic energy sources. Hydraulic energy is available wherever there is a flow of liquid and accumulated head. Head represents potential energy and is the vertical distance through which the fluid falls in the energy conversion process. The type of turbine selected for a particular application is influenced by the head and flow rate. There are two classifications of hydraulic turbines: impulse and reaction. The flow through the turbine is controlled by wicket gates on reaction turbines and by needle nozzles on impulse turbines. A turbine inlet valve or penstock intake gate is provided for isolation of the turbine during shutdown and maintenance.
