Adopted from the existing standalone Ocean Treader hydropower generator to work in conjunction with existing or future offshore wind turbines, Wave Treader is designed to piggy back on top of much of the existing wind turbine infrastructure for maximum efficiency. It can generate up to 500 kilowatts of power, improving the electrical yield per area of sea compared to solely deploying wind turbines in the same locations.
The Ocean Treader uses a floating spar buoy as the primary structure supporting the generator in the sea. The Wave Treader uses the base of the wind turbine in the same role. Two steel arms with glass-reinforced plastic floats at the end are attached to the turbine. When passing waves lift and lower the arms, the pressurized hydraulic fluid inside mounted hydraulic cylinders drives a hydraulic motor which in turn drives an electric motor generating usable power sent on for distribution. The arms can rotate to best take advantage of the direction of waves and also can rise or fall vertically to account for tidal range (the difference in the water level between low tide and high tide).
Because these power generators are deployed in remote areas, reliability is very important. The Wave Treader is designed from standard marine off the shelf components that are well tested and designed to limit single points of failure as much as possible. Duplication is built in, allowing for continued use even if something does damage or fail. Furthermore, the extra load on the wind turbines is minimal and should not adversely affect the system's reliability or performance. The Wave Treader is rated for 25 years of service with five year periods between refits.
A full size prototype of the Wave Treader is planned towards the end of this year with production planned for 2011.
TFOT has previously reported on other innovative wave power and hydropower generators including the VIVACE generator that generates power from vortex-induced vibrations found in rivers and other waterways with currents. You are also welcome to read our coverage of an oscillating water column that uses waves to force air into turbines, and the Anaconda snake-like rubber tubes that use bulge waves to generate power. TFOT has also reported on several offshore wind turbines including the HyWind floating wind turbine, the super efficient Selsam SuperTurbine, and a deep water floating wind turbine.
Read more about the Wave Treader hydropower attachment on the Green Ocean Energy page devoted to the project.