Principle Power is a Seattle, Washington-based renewable energy technology company that developed WindFloat, an offshore wind power turbine and platform. The platform can be assembled on shore and then towed to a site offshore where it is moored and connected to a power station.
Principle Power recently deployed its first WindFloat system off the coast of Portugal, the first offshore turbine to be located in open Atlantic waters (read more about the first deployment here and here).
The WindFloat technology is described in U.S. Patent Application Publication No. 2011/0037264, entitled “Column-stabilized offshore platform with water-entrapment plates and asymmetric mooring system for support of offshore wind turbines” (’264 Application).
The platform comprises columns (102, 103) interconnected with a truss structure composed of main beams (115), bracing beams (116), and cross beams (117). A wind tower (111) is attached to one of the base columns (102, 103).
A wind turbine (125) is attached to the wind tower (111). At the base of the columns are horizontal water-entrapment plates (107). The submerged plates (107) are designed to provide hydrodynamic added-mass and dampening, resulting in reduced platform motion – particularly in heavy seas.
The turbine platform can also include active ballast systems for stabilization. The columns (102,103) can be hollow and and house the active ballast system, which transfers water between tanks within the columns. The active ballast system is designed to keep the mean position of the platform horizontal and to keep the turbine as upright as possible.
According to Principle Power, unlike conventional offshore wind turbines, the stabilization features of the WindFloat allow the platform to withstand the high wind and wave energy found in deeper waters. Wind turbines located far from shore overcome disadvantages of their close-to-shore counterparts because they do not block the shore view and lessen navigational obstructions and potential hazards to water vessel and aircraft while tapping into previously inaccessible wind resources.
Article by David Gibbs, a contributor to Green Patent Blog. David is currently in his third and final year at Thomas Jefferson School of Law in San Diego. He received his undergraduate degree in Geology from the University of California, Berkeley.