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Power and Energy Directly from Water
Turbine and generator
Low force
High velocity
High force
Low velocity
Air–water interface
(a)
Overtopping
Reservoir
Turbine outlet
(b)
Top view
Side view
Wave direction
Wave direction
(c)
FiGUre 13.2 Types of WECs: (a) oscillating water column; (b) overtopping WEC;
(c)  attenuator WEC; (Adapted from “How hydrokinetic energy works?” Union of Concerned
Scientists, 1–5, 2012.)