Dual-fuel ship refueling

[PlanoTim]

I have seen a post or two recently about a couple of Carnival’s dual-fuel ships leaving their home port late due to refueling delays.  I certainly don’t know if this is related to the ships being dual fueled.  Do dual-fuel ships - powered by liquefied natural gas (LNG) and traditional marine fuel oil - take longer to take on fuel than traditional ships?  I don’t think this has impacted any itineraries, but I’m wondering if this is an LNG refueling issue?  Can a ship take on LNG and bunker fuel at the same time?  Do dual-fuel ships take on LNG after every cruise?  I believe Carnival has three ships that are dual fuel - Carnival Celebration, Carnival Mardi Gras, and Carnival Jubilee.  Just wanting to understand the new technology better and trying to understand how LNG impacts the fueling of these ships.

[Haljo1935]

@Heidi13 @chengkp75 are either you able to provide insight?

[hurricane0226]

Was on the Mardi Gras in November, there were done refueling with LNG, by 3:00pm this I know,

excuse me for this, but ( we were able to smoke then. ) sory. 

[Heidi13]

10 hours ago, Haljo1935 said:

@Heidi13 @chengkp75 are either you able to provide insight?

 

Sorry, can't help much with this one, as I don't know much about the Carnival fleet, or even where they homeport. Assuming it is new tonnage, as I don't recall reading of the conversion of existing ships, I would expect the system would be designed to be capable of loading the required bunkers within a normal turnaround. Since Carnival ships tend to sail shorter itineraries, they are in homeport frequently, so I would expect the cruise line has also ensured the local infrastructure is capable of supplying the required bunkers in the available time.

 

My last ship, which was converted to LNG about 10-years ago, has not had any bunkering issues or delays.

[chengkp75]

If the ship is taking both MGO/HFO and LNG from barges, then they won't be able to bunker both at the same time.  I know that PEV has plans for a storage facility planned, but I don't know whether this has been completed or not.  That would perhaps allow simultaneous bunkering, it all depends on the amount of crew available, and the Chief Engineer's comfort with simultaneous operations.  LNG bunkering takes a lot of preparation work, especially if the tanks are completely empty (pre-chilling the tank).  

 

I believe that the ship's don't have that much LNG tank capacity, so they most likely bunker the LNG weekly.  The MGO is only about 5% of the fuel mix, so that would more likely be bunkered monthly or every other month.

 

If they are using barges for LNG, there is always the possibility of delays with the barge getting there.

[chengkp75]

Let me add that the possibility of simultaneous bunkering would also depend on the company's Safety Management System policies and procedures, as well as USCG Captain of the Port regulations.

[tidecat]

When I was on Mardi Gras, they started refueling during debarkation. So if the barge or the ship is late, then that can affect departure.