Fall power plants:
A fall powerplant is a hydroelectric power plant which uses water, piped down a hillside to trigger a Pelson turbine ( Most of the time ). A Pelson turbine is also called a free-jet turbine or Pelton wheel, a type of impulse turbine. Water passes through nozzles and strikes spoon-shaped buckets or cups arranged on the periphery of a runner, or wheel, which causes the runner to rotate, producing mechanical energy. The runner is fixed on a shaft, and the rotational motion of the turbine is transmitted by the shaft to a generator. Pelton turbines are suited to high head, low flow applications. Typically, to work this type of turbine, water is piped down a hillside so that at the lower end of the pipe it emerges from a narrow nozzle as a jet with very high velocity. The Pelton turbine can be controlled by adjusting the flow of water to the buckets. In order to stop the wheel a valve is used to shut off the water completely. Small adjustments, necessitated by alterations in the load on the generator, are more safely made by a device which deflects part of the water jet away from the buckets.
The biggest in the world:
The largest of these fall power plants is The Henry Borden complex, located on the foot of the Serra do Mar, in Cubatão in Brazil. It encompasses two high (720 m) fall power plants, called External and Underground, with 14 groups of generators, powered by Pelton turbines, totaling an installed capacity of 889 MW, for a flow rate of 157 cubic meters/s.
Similair large power stations of this type can be found here near Urfeld in Bayern, Germany (this one produces a power of 124MW ),
Here near the famous sight of Machu Picchu in Peru. The 100 MW plant, built by Alstom, supplies the famous Inca region with electricity:
Here near khopoli in India the Tatu hydroelectric power station is situated. This one is 4 km long, it begins here and it ends all the way down here. And here in Bhira in India is another large one ( 150 MW ). Which is called the Bhira hydroelectric power staton:
Thursday, January 22, 2009
Fall power plants: