Filak calls his design the U.S. Spar Buoy (USSB) foundation and recommends building it using a geopolymer concrete. Geopolymer is a material that, unlike steel, does not degrade in seawater. The Zeobond Group in Australia is one manufacturer of the material. Reinforcement would come from a corrosion-resistant, steel-free rebar.
Construction begins and ends on an ocean-going deck barge built to construct the spar buoys and deploy them to a deep-water wind farm.
Buoy construction is executed dockside. The first component, an end-bell starter section, measures 40-ft diameter by 30-ft high. This first component is cast on the dock and then set into a lowering well on the barge. The slip formwork and its staging are placed in four pie-shaped quadrants onto the end-bell starter.
The deck plan (a top view) shows on the left, winch cables and the spar buoy work area, and on the right, where the transition piece and wind turbine would be assembled. The dual-hull catamaran barge measures 480-ft by 60-ft wide connected by a bridging structure 300-ft by 50-ft by 10-ft deep flush with the deck plate and centered fore and aft on the outside hulls. This provides a deck plan of 72,600 ft2