Moored Substructure Installation Methodology

For details of the code implementation, please see the Moored Substructure Installation API documentation

Overview

The MooredSubInstallation module simulates the manufacture and installation of moored substructures for a floating offshore wind project. The installation procedures include the time required to manufacture a substructure at quayside, assemble a turbine on the substructure, ballast the completed assembly, tow the completed assembly to site and hook up the pre-installed mooring lines.

Configuration

The primary configuration parameters available for this module are related to the quayside assembly process and the vessels used to tow the completed assemblies to site and complete the installation. The code block highlights the key parameters available.

config = {

    ...

    "ahts_vessel": "example_ahts_vessel",    # Anchor handling tug supply vessel associated with each tow group.
    "towing_vessel": "example_towing_vessel",    # Towing groups will contain multiple of this vessel.
    "towing_groups": {
        "towing_vessel": 1,  # Vessels used to tow the substructure to site.
        "ahts_vessels": 3,  # Number of anchor handling/station keeping vessels
        "num_groups": 1  # Number of independent groups. Optional, default: 1.
    },

    "port": {
        "sub_assembly_lines": 2,  # Independent substructure assembly lines.
        "sub_storage": 8,         # Available storage berths at port for completed substructures.
        "turbine_assembly_cranes": 2,  # Independent turbine assembly cranes.
        "assembly_storage": 8,    # Available storage berths at port for completed turbine/substructure assemblies.
    },

    "substructure": {
        "takt_time": 168,   # h, time to manufacture one substructure.
        "towing_speed": 6,  # km/h.
    },

    ...
}

Processes

Quayside Assembly

Process	Default
Substructure Assembly	168h
Prepare Substructure for Turbine Assembly	12h
Lift and Fasten Tower Section (repeated if necessary)	12h
Lift and Fasten Nacelle	7h
Lift and Fasten Blade (repeated)	3.5h
Mechanical Completion and Verification	24h

Substructure Tow-out and Assembly

Process	Default
Ballast to Towing Draft	6h
Tow-out	calculated
Ballast to Operational Draft	6h
Connect Mooring Lines	22h
Check Mooring Lines and Connections	12h