Scalable devices that run parallel to the direction of the waves, enabling the absorbtion of most of the energy of the waves. The motion of the device moves hydraulics, which pressurizes oil. This pressurized oil moves through hydraulic motors, which power electric generators. These devices are loosely tethered to the sea floor and send electricity back via sea floor laid cables.
Click on the links below to learn more about examples of Attenuators, including the Pelamis Wave and Salter’s Duck.
Oscillating Water Column
This device takes advantage of the movement of air of waves. As a wave enters the chamber, it pushes the air in the chamber up a column and spins a turbine mounted inside the column. As the wave recedes/moves back into the ocean, it sucks air back out, thereby taking air out of the column which spins the turbine in.
Click on the links below to learn more about examples of Oscillating Water Column devices, including the LIMPET and Oceanlinx.
These devices channel waves into reservoirs, which fill to levels above those of the surrounding water. Gravity then makes the water fall back to sea level, but it passes through a hydroelectric turbine before re-entering the ocean. Overtopping devices can be seadwelling devices or built into the coast.
Click on the links below to learn more about examples of Overtopping, including the Seawave Slot-Cone Generator and the Wave Dragon.
Point Absorber (buoy)
This is a scalable, floating structure similar in design and purpose as a navigational buoy, that moves up and down with the passing waves. This technology seems to be the most widespread and has the greatest degree of variance in electricity production methodology, where water pumps, magnets and hydraulics are used. Those using water pumps can also produce electricity on each buoy or be pumped back to shore as part of a desalinization system.
The types of Point Absorbers vary the most, as they can be floating or fully submerged, or generate electricity through a magnetic generator, onboard or onshore hydroelectric turbine. Those that pump the pressurized seawater to shore can also be used for water desalinization. Click on the links below to learn more about examples of Point Absorbers, including the AquaBuOY, CETO and Oregon State’s Permanent Magnetic Linear Generator Buoy.