The Netherlands: GeoSea Launches Self-Elevating Heavy-Lift Jack-up Vessel ‘NEPTUNE’



The launch ceremony for the self-elevating heavy-lift jack-up vessel NEPTUNE took place on 23 September 2011 at the IHC Merwede Shipyard in Krimpen aan den IJssel, The Netherlands.

This jack up vessel is built by IHC Merwede for GeoSea N.V., the offshore marine construction specialist of the DEME Group of Belgium.

The contract for the detailed design, construction and delivery of the vessel was signed between GeoSea and IHC Merwede on 16 September 2010 and the keel was laid on 25 March 2011. The vessel will be operational in the first quarter of 2012. A short delivery time for this complex, high-tech and unique vessel.

The 60-metre long and 38-metre wide DP2 (dynamic positioning) self-propelled jack-up vessel is equipped with a dedicated 600-tonne crane that is fully integrated into the hull. The Neptune will be perfect for the transport and installation of offshore wind turbines and any other heavy marine offshore structures. Once operational, the Neptune will be provided with a Green Passport, delivered by ABS (American Bureau of Shipping).

On delivery to GeoSea in early 2012, the Neptune will start its first assignment on the Thornton bank off the Belgian coast, where it will perform the installation of the 48 wind turbines for the second and third stages of the C-Power offshore wind farm. Then, the Neptune will move to German waters in the North Sea for the construction of both the Trianel West Borkum II wind farm (45 km north of the East Frisian Island Borkum) and the EnBW Baltic 2 wind farm (32 km north of the island of Rügen).

The new jack-up vessel has been given the name Neptune as this god of the seas represents the universal ocean of oneness with all beings. Therefore, Neptune is strong, unyielding, indomitable, idealistic and imaginative. Neptune is also considered to be a planet of inspiration, dreams and creativity. All these characteristics are an ideal match for GeoSea’s aims and values.

 Additional information

Main features:


Length 60.0 m

Breadth 38.0 m

Depth 6.0 m

Design draft hull 3.90 m


Number 4

Type circular section, diameter 3.50 m

Leg length 92.00 m

Jacking system

Type GustoMSC hydraulic positive engagement

Drive Electric-hydraulic

Capacity 2750 t preload per leg


600mT Wind Turbine Installation Crane (make Huisman)

10 mt Auxiliary Crane


Thrusters 4 x azimuthing dismountable thrusters with CPP propellers, 2 aft and 2 forward

Propeller diameter 2,30 m

Drives 4x diesel engine 1.600 kW each


Accommodation for 60 persons


ABS for self propelled vessel (IMO MODU Code)

Class notation: ABS +A1, Self Elevating Unit, +AMS, +ABCU, DPS-2, CRC


Source: deme, September 23, 2011