Service and accommodation vessel combines elements of CTV and SOV

Penguin Shipyard in Singapore has delivered the offshore wind industry’s first service accommodation and transfer vessel (SATV). The vessel is destined for use in Taiwan’s fast-growing offshore wind industry on the Formosa 1 offshore windfarm.

Ventus Formosa is a 35-m aluminium vessel designed by BMT in the UK. The vessel is purpose-built for 12 windfarm technicians to live aboard for up to a week.

Unlike regular crew transfer vessels, which are smaller and serve as ‘point-to-point’ shuttle vessels, the service accommodation and transfer vessel (SATV) is a fully equipped, live-aboard vessel that enables technicians to live comfortably on board without requiring daily port calls.

The keel of the vessel was laid in March 2019. It was built for Ventus Marine, a joint venture (JV) between PSA Marine and its Taiwanese partner Ta Tong Marine Group.

The JV is leveraging experience gained by Njord Offshore Ltd, a leading crew transfer vessel operator with significant experience in managing crew transfer vessels in Europe. The JV first worked in the offshore wind sector with 26-m CTV Ventus Beigang, which can carry 12 passengers.

The somewhat larger SATV the JV ordered is capable of remaining offshore for at least seven days and will have 12 single cabins for wind turbine technicians. It will be registered under the Taiwanese flag and manned by Taiwanese crew trained by Njord Offshore.

The design of the new SATV aims to push the boundaries of windfarm servicing and maintenance activity and provide a high level of operational versatility, providing long-term offshore accommodation while still being able to push up against a turbine to transfer technicians. The vessel does not require an offshore access ‘walk-to-work’ system.

This flexibility provides a much more efficient operational profile for servicing turbines located further offshore and from the main ports, BMT said in earlier statements about the design.

BMT has stated that the vessel uses its patented active fender system (AFS). The AFS is available in various sizes and has been developed specifically to meet the market needs for larger transfer vessels. The AFS maintains impact loading when pushing against a turbine within safe operational limits, thus ensuring the vessel can engage correctly and ensures improved and continuous contact between the vessel and the turbine allowing for safe transfers.

Passenger comfort has been optimised by ensuring all sleeping accommodation space is above the main deck level where noise levels will be kept to a minimum through using a resiliently mounted super structure, both of which are said to be a first for a transfer vessel of this size.

Powered by twin MTU 16V2000 engines coupled to a Servogear controllable pitch propeller propulsion system, the SATV will transit at a speed of 19 knots and cruise at a speed of 16 knots, with a deadweight capacity of 65 tonnes.

Speaking at the time the SATV was ordered, Njord Offshore managing director Tom Mehew said “The SATV offers a new logistical model which will enable technicians to be accommodated offshore and also transfer directly onto the turbines like our existing crew transfer vessels without the need for an expensive gangway system which will ultimately save time and money for our client.

“With the SATV, we are offering a new offshore wind service solution. The vessel concept fits the bill perfectly for projects like Formosa 1. A full 40-person service operation vessel would be oversized, and standard CTVs would be undersized.”

The SATV also allows the owner and Siemens Gamesa to safely and efficiently address the challenging tidal conditions found in the Taiwan Strait.