VESSEL REVIEW | Umo Green – Trimaran crewboat to serve Taiwanese offshore wind market

Danish offshore services provider World Marine Offshore (WMO), through its Taiwan-based joint venture company U-Ming Marine Offshore (UMO), has begun operating a new windfarm support trimaran crewboat built by Thai shipyard Marsun.

Designed by naval architecture firms WIND of Denmark and One2Three of Australia, Umo Green is the first in a series of two to be built by Marsun for WMO. The newbuild has all-aluminium construction, an LOA of 30.5 metres, a beam of 11 metres, a maximum draught of two metres, a displacement of 185 tonnes at full load, and capacity for 20 tonnes of deck cargo and 24 technicians in addition to the five crewmembers.

Three MAN D2862 1,066kW engines driving Hamilton waterjets via ZF gearboxes propel the crewboat to a top speed of 29 knots and a service speed of 25 knots. WMO said the use of three waterjets – with one in each of the three hulls – ensures a high bollard push of 17 tonnes and excellent manoeuvrability. Marsun added that the engine room has been prepared for future hybrid conversion, allowing an electric motor to be installed in the driveline to further enhance operational flexibility.

The trimaran design also enables safe operation even in significant wave heights of up to two metres. The optimised hull form guarantees inertia to help compensate for sudden wave motion even during extended periods offshore.

A crane with a lifting capacity of 890 kilograms is installed on the foredeck to aid in the loading and unloading of cargo during resupply trips. Fendering from Softbow is also fitted. Below the foredeck is a climate-controlled storage facility for additional cargo.

Other onboard facilities include two officer cabins, two double crew cabins, a mess, and a lounge. The crew and passenger spaces benefit from noise levels well below 60 dB even while underway due to the low vibration of the waterjet propulsion and the superstructure being fitted on resilient mounts.

Umo Green is classed by both Bureau Veritas and Taiwan's CR Classification Society and designed in compliance to both Danish flag requirements and the IMO's HSC code guidelines. UMO will soon begin operating the crewboat on a long-term contract with an undisclosed charterer in Taiwan.