Wave-energy
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Source:dpa, Die Welt
Video clip: Oscillating water column
S o u r c e :
https://www.youtube.com/watch?v=gcStpg3i5V8&list=PL1BCA44C365504B48
&index=2
Two different types of turbines are used to convert the energy. One is a Wells-
type turbine which is mostly used. A Wells turbins looks like an airfoil with a
symmetric profile. But due to the symmetry the turbine has a poor efficiency. It
uses the physical principle of a hydrostatic uplift, called buoyancy. A Wells
turbine can be attacked from both sides so that it has a consistent turning direction.
Principle of a Wells turbine
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The second type of turbines used in an open water column power plant is an
annaabi.ee 
