Norway-based Siem Offshore has contracted Remontowa Shipbuilding S.A. in Poland to build four dual-fuelled Platform Supply Vessels (PSVs). The vessels are to be of VS 4411 DF design, and Siem Offshore say that they currently have two vessels of similar design under construction for delivery in 2014 and 2015. The new PSV's will be equipped with dual-fuel LNG or Marine Diesel Oil (MDO) systems which Siem Offshore claim to represent the latest technology of dual fuelled systems and hull design,giving benefits of lower fuel consumption, lower fuel cost, lower emissions and a better environment.