Wave Energy Concept

The video below presents a device to capture energy in ocean waves that consists of a tube under the water, open at both ends, and using the water that oscillates back and forth inside the tube to drive a turbine.  Note that the device is not shown actually working in water; there is a reason for that: the actual motion of the water falls off sharply as one descends down into the water.  In fact, below the “wave base” (half of the wavelength beneath the equilibrium point), there is no motion at all, as explained in “Ocean Wave Basics.”