Houlder develops windfarm mother ship designVessel & ROV News // January 21, 2011
Houlder in the UK says it has developed the design of an infield windfarm mothership concept for the Carbon Trust's offshore access competition. The design was developed by Houlder's specialist design subsidiary, Hart Fenton & Company.
The concept's key purpose would be as an operation and maintenance (O&M) mothership, with the vessel providing accommodation, workshops, hotel services, storage and a five-tonne lifting capacity. The vessel will be designed so that it can remain on station for a minimum of seven years.
A source at Houlder told ODS-Petrodata that discussions were ongoing with developers and utilities, as well as the Carbon Trust, over the concept. Current specifications for the concept would see it having a length of 89.6m, breadth of 20m and accommodation for 12 marine crew and 48 workers.
The barge-shaped hull would not have propulsion and is intended to be moored to a single buoy mooring system down weather of the prevailing wind. This would allow the vessel to weather vane and encounter wind and waves on the bow, and effectively remove the roll element from the vessel motions, leaving the vessel to pitch and heave.
The company says that with relatively short seas, these motions should be acceptable to up to 60 persons living on board.
The hull of the vessel would have landing recesses in its side to allow workboats to dock alongside. The vessel would also be fitted with an open safe haven in the stern to protect workboats, and have a launch and recovery system to allow the workboat to be stowed on board during rough weather. The vessel would also be fitted with a small helicopter deck to allow for emergency helicopter landings.