Offshore Supply Vessel "Viking Queen". Courtesy of Eidesvik

It’s always good for an office rat to get out of the office and take a closer look at some real equipment. So I appreciated very much my opportunity last week to visit the Viking Queen and learn about the technical choices and the experiences with this quite unusual ship.

First, some background: The Viking Queen is a 6000 ton supply vessel delivered to the shipowner Eidesvik in 2007. The ship’s purpose in life is to supply goods to offshore installations in the North Sea. It is unusual in at least two aspects: It has its accommodation area aft, and it is powered by LNG.

The first impression I have from the visit, is that the ship and its crew disproves the typical myth that LNG adds a lot of complexity to ship systems and associated operations. The picture series below starts at the bunkering station on deck where LNG is received through flexible cryogenic hoses from the quay. There are no requirements to double wall piping above deck, but inside the ship the piping needs to be routed inside bigger steel pipes. The fuel tank is a type C tank, which is inherently safe, and it is located in an area onboard where collisions will not harm it. From the tank, the LNG enters the cold box, which contains the pressure build up unit (PBU) which re-gasifies the LNG. As the fuel piping enters the engine room, the double wall piping requirement is substituted by a gas detection and ESD system, making the routing of pipes much simpler. The gas is routed through a few filters, and then into the engine combustion chambers. No pumps are involved, and no fuel treatment is necessary.

The second impression is related to the spirit of the crew. Clearly they are proud of their ship. A consequence of this of course is that everything is clean and tidy. No clutter around. And the crew are genuinely interested in the engines, systems, and equipment, making them much more likely to understand what is going on than an average crew. This is something I also observe with a slight touch of concern: There are no international or national legislation for training or skills of crew specifically related to LNG. Eidesvik has approached this by developing their own set of operational procedures and training requirements for their crew. Which is all good. But my concern is that not every ship operator in the world would be as proactive as Eidesvik in this respect.

A common question I get when speaking about LNG fuelled ships is “what about maintenance? Is it less maintenance with them?” I still don’t have any statistics to put forward on this topic, but on a qualitative basis, the feedback from Eidesvik was very positive:

• The engine and the systems themselves are very clean, reducing the need for cleaning before doing maintenance activities.
• There is less particles and corrosive components in the system, leading to reduced need for preventive maintenance. They have no increased maintenance intervals on certain components, and there is room for more of this.
• Eidesvik reported no LNG-related downtime on of their ships.

As stated by the chief onboard, “The Viking Queen is a better ship”. I would like to extend a thanks to Eidesvik, both their management, and particularly the crew onboard for openly sharing their experiences. And with LNG fuelled ships in operation since 2003, who would have more experience to share than Eidesvik?

The bunkering station on deck. A flexible hose from shore is connected to onboard flanges.

The LNG tank with isolated walls to minimize heat ingress from possible fires in neighbouring areas

Piping exits the double wall tube as it enters the engine room. The engine room is ESD protected so there is no need for double wall piping inside the engine room