A thermal power station is a power plant in which the prime mover is steam driven. Water is heated, turns into steam and spins a steam turbine which drives an electrical generator . After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was heated; this is known as a Rankine cycle . The greatest variation in the design of thermal power stations is due to the different fuel sources. Some prefer to use the term energy center because such facilities convert forms of heat energy into electricity.  Some thermal power plants also deliver heat energy for industrial purposes, for district heating , or for desalination of water as well as delivering electrical power. A large part of human CO 2 emissions comes from fossil fueled thermal power plants; efforts to reduce these outputs are various and widespread. whereas Hydropower or water power is power derived from the energy of falling water, which may be harnessed for useful purposes. Since ancient times, hydropower has been used for irrigation and the operation of various mechanical devices, such as watermills , sawmills , textile mills, dock cranes , and domestic lifts . Water 's power is manifested in hydrology , by the forces of water on the riverbed and banks of a river. When a river is in flood, it is at its most powerful, and moves the greatest amount of sediment . This higher force results in the removal of sediment and other material from the riverbed and banks of the river, locally causing erosion , transport and, with lower flow, sedimentation downstream.
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