Siem Offshore has again contracted Wärtsilä to supply the design and integrated solutions for four new platform supply vessels (PSVs). The ships will be built at the Remontowa Shipbuilding yard in Poland. The contract was signed in January 2014.

The four new vessels, like the two currently under construction, will utilise the Wärtsilä VS 4411 DF ship design and will have Wärtsilä dual-fuel propulsion allowing them to operate primarily on liquefied natural gas (LNG). With the various Wärtsilä systems having been integrated into a total solution, and with an optimised hull design, the vessels will feature lower fuel consumption, reduced fuel costs, and fewer exhaust emissions compared to vessels running on conventional marine fuel.

Wärtsilä will also supply the complete diesel electric system, the Wärtsilä LNGPac gas storage and handling system, and the complete electrical and automation system, including a four-split Wärtsilä LLC (Low Loss Concept) solution. The Wärtsilä LLC will enable the vessels to fulfill the highest possible Environmental Regularity Number (ERN) of 99.99.99. The ERN rating represents the capability of a vessel to maintain its position and normal operations under certain weather conditions. Wärtsilä is the first supplier capable of providing such a high ERN.

“This repeat order emphasises again the efficiency and customer benefits of Wärtsilä’s unique position as a total solutions provider. These PSVs will often be working in challenging sea conditions, and in areas where strict emissions regulations are in place. Our integrated systems solution and dual-fuel technology that allows the ships to run on clean LNG fuel, enable such challenges to be met and overcome,” says Magnus Miemois, Vice President, Wärtsilä Solutions.

The four new PSVs will be built to the highest requirements for operations on the Norwegian Continental Shelf. They will have an overall length of 89 metres, a beam of 19 metres, a deck area of 970 m2, and a capacity of 5,500 dwt. They are scheduled for delivery between third quarter 2015 and second quarter 2016.

Siem Offshore is based in Norway and is a leading provider of marine services to the oil and gas industry.