Over the past two years, there has been a notable upsurge in debate regarding how best to serve those technicians servicing European offshore wind farms particularly those located at the Round 3 developments, situated miles offshore and often in water depths of 25-65m.
One popular proposal has been the deployment of motherships, or ‘floatels’, at the sites in the deepest waters, thereby sparing offshore workers excessively early morning shore-to-site commutes and the subsequent risk of fatigue and seasickness. Similarly, by keeping technicians on-site, companies could realise significant fuel savings and a wider operational window reducing the likelihood of wasted shore-to-site trips, should rough weather or wave conditions rule out the possibility of safe personnel transfer at the turbines.
Active since 2008, Netherlands-based shipowner C-bed has come to amass a fleet of three large floatels, the most recent of which, Wind Innovation, entered service in February this year.
However, unlike many offshore accommodation providers, C-bed’s strategy has been to renovate and customise existing vessels for this purpose, rather than ordering new tonnage from scratch. The owner’s other floatels, Wind Solution and Wind Ambition, were rebuilt in 2008 and 2010 respectively, while a former asset, Wind Perfection, was retired and sold last year. Following suit, Wind Innovation was formerly recognisable, until recently, as Eidesvik Shipping’s 93.4m, 3D seismic survey vessel Viking II; now, though, she comprises an 80-cabin, four-star floating hotel for offshore personnel.
Flemming Hjorth, senior sales executive at C-bed, tells Offshore Marine Technology: “Repurposing existing vessels is not so much related to cost we can save significant amounts of time through converting vessels, rather than ordering newbuilds.” This strategy grants C-bed the ability to quickly meet demand from the energy majors and their trusted operator customers in a market where vessel availability is crucial in securing charter arrangements.
Despite having 80 single cabins for technicians, Hjorth explains that Wind Innovation can be configured for 90 berths, if needs be. This complement is lower than that of her fleet sisters Wind Solution and Wind Ambition can accommodate between 120-150 persons, for example. However, there has been no skimping on luxury it is important to ensure that these technicians (for some of whom, it may be their first time located ‘offshore’ for an extended period) are comfortable and happy in their surroundings, as a means of staving off boredom, claustrophobia, fatigue and loss of concentration.
Each cabin comes with its own bathroom/toilet facility, desk and wardrobe, and occupants have access to TV and internet. Elsewhere on the vessel, C-bed has installed a restaurant area, a games room, a cinema, a gym and a TV lounge, in addition to offices and a meeting room for discussion of work-related matters.
“We made sure that most of the single cabins have windows, to let in natural light,” says Hjorth. “However, we also realised that some of the crew may be working night shifts, and need to sleep during the day. So, Wind Innovation also incorporates sheltered cabins, which won’t let in bright light. We also made sure that new cabin rooms were situated away from the engine room and helipad, to keep noise levels to a minimum in that area.” Instead, the offices have been situated beneath the helipad, which features a diameter of 22.2m and a weight capacity of 11.9tonnes.
Focus on transfers
Wind Innovation is the first C-bed vessel to feature a motion-compensated, hydraulic ‘walk to work’ (W2W)-style gangway for safe technician ship-to-turbine transfers in rough weather.
Hjorth says that, whereas more traditional crew vessels can conduct safe transfers in significant wave heights of 1.5-1.75m, the presence of the W2W system permits safe technician transfers in conditions of up to 2.5m Hs. Should, for any reason, use of the gangway not be viable, or should crew and technicians require an emergency response (for instance, in the case of a man overboard incident), Wind Innovation has also been developed with its own purpose-built boat landing, for transfer of personnel via smaller crew transfer vessels (CTVs). Typical, fit-for-purpose CTVs include 12-pax and 24-pax models; Damen’s 25.7m ‘Twin Axe’ fast crew supplier and Northern Offshore Services’ 27.2m ‘Developer’ model would constitute ideal fits for Wind Innovation, for instance.
All C-bed vessels operate under the UK flag, in recognition, Hjorth says, of “the strong requirements of the UK regulations”. Now, Wind Innovation is beginning her new life as an accommodation block at the 600MW Gemini wind farm, located 85km from the coast of Groningen in the North Sea, and her fleet sisters will join her in this territory soon.
And, although there are no specific plans to introduce a fourth floatel at present, Hjorth says that C-b is experiencing significant interest from leading operators across the oil and gas segment, as well as the offshore wind sector prompting the group to look for new opportunities. Future renovated vessels may incorporate features such as the presence of daughter craft, large motion-compensated cranes and helicopter hangar and fuelling facilities, he hints.