A new type of ship is boiling in the emerging market of Offshore Wind Farms: the Windfarm Mother Ship. This type of vessel is designed as a mother ship which would remain on station in offshore deep-water wind farms, providing a safe haven for catamaran workboats to carry engineers to service turbines.
· Sea-Wind WMV, by Offshore Ship Designers. This concept is a submersible dock ship with a large floodable dock accessible from the stern. The vessels will be fitted with energy efficient diesel-electric power generation and propulsion systems and will use a number of renewable energy devices to supplement the power generation and support systems, reducing the overall carbon footprint of the vessel. The largest version of the design will be around 187m overall length, it will be fitted with a DP2 dynamic positioning capability, and it will have accommodations to cater for up to 200 persons.
· O&M Mother Ship, by Hart Fenton. This vessel will be designed so that it can remain on station for a minimum of seven years. The barge-shaped hull would have no self-motion capability 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. Current specifications for the concept would see it having an LOA of 89.6 metres, a breadth of 20 metres and accommodation for 12 marine crew and 48 workers.