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This paper presents the design and analysis of a mooring buoy and its mooring systems to moor a floating platform mounting an arrayed Wave Energy Converters (WECs). The mooring buoy allows the WEC platform to weathervane around the mooring buoy freely by the prevailing environment directions, which enables consistent power generation. The WEC platform is connected to the buoy with synthetic hawsers, while station-keeping of the buoy is maintained with catenary mooring lines of chains tied to the buoy keel. The buoy also accommodates a power cable to transfer the electricity from the WEC platform to the shore. The WEC platform is designed to produce a total of 1.0 MW with multiple WECs installed in an array. Fully coupled time-domain analyses are conducted under the site sea states, including extreme 50 y and survival 100 y conditions. The buoy motions, mooring tensions and other design parameters are evaluated. Strength and fatigue designs of the mooring systems are validated with requirements according to industry standards. Global and local structural designs of the mooring buoy are carried out and confirm the design compliances.

Increased attention has recently been focused on determination and reproduction of realistic properties of extreme sea waves for use in numerical and physical modeling and design load computations. Results of recent research on laboratory synthesis of extreme waves and experimental investigation of wave-fluid particle kinematics just prior to breaking using laser Doppler anemometry is presented. An extreme transient wave, similar to those found in hurricane Camille, and an "equivalent" regular Stokes wave often used for design purposes were generated, and their kinematics measured.Due to particular asymmetries not present in the Stokes wave, the transient wave kinematics under the crest are shown to be much more severe above the still water level and somewhat less severe below. This comparison suggests that it would be worthwhile to further investigate the use of extreme, transient waves as new, more realistic design waves.

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