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Floating Production Solutions

D-Spar & Fork-on/Float-off installation methods

For the rapidly maturing offshore wind farm industry, MODEC has innovated a revolutionary floating substructure and its associated installation method. MODEC foresees the potential of Spars as one of the floating substructure concepts for the offshore wind industry, as the fabrication cost would be advantageous for ever increasing size of Wind Turbine Generators. MODEC’s new Spar concept and its installation methods would further enhance the advantages of the Spar by offering a broader selection of the assembly and installation sites. D-Spar concept and Fork-on/Float-off installation methods are patented inventions of MODEC.

Disconnectable System

This innovative connection system enables the connection/disconnection of the entire Wind Turbine assembly from the Spar at the offshore site.

Inspired by a proven

Disconnectable FPSO Mooring System

This has been one of the standard systems for FPSOs in Cyclone prone areas. Based on this technology, MODEC develops safe and cost effective disconnectable system for the offshore wind facilities.


FPSO MODEC Venture 1 in Australia &
Disconnectable Riser Turret

Fork-on / Float-off Installation Methods

The wind turbine and its tower can be fully assembled and commissioned onshore, and then transported to the site as one complete assembly. Twin “forks” extended from transportation vessel will pick up the assembly, transport it to the offshore site, and hold it in position while the preinstalled Spar is pulled up between the twin forks and connected to the tower. The complete assembly will be floated off the forks during this operation. This operation can be reversed/repeated in the unlikely event of  a major malfunction of Wind Turbine Generators requiring maintenance..



The D-Spar has been nominated as one of the final three candidates for “HYWIND® Installation Challenge”,

* HYWIND is a registered trademark of Statoil.