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About chengkp75

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    Former cruise ship Chief Engineer

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  1. The cryogenics is a static system. The tanks essentially have a vacuum bottle around them, and this keeps the LNG cold. The vacuum insulation works very well, and LNG tankers sail from the US to Asia without doing anything to the cargo. The little heat that does get into the tank causes a small amount to boil off, and this gas is taken as fuel for the engines, this is typically estimated as 0.1-0.25% of the tank volume per day. If there is too much boil off, a relief valve will lift, and gas will be vented high up above the ship. A ship relying on LNG as primary fuel will actually draw off more than this, gasifying it as needed to fuel the engines. Cryogenic tanks typically have a pressure of only 3-4 psi as opposed to a bus fuel tank at 145 psi - 180 psi (dependent on ambient temperature). Ships can also use re-liquifaction equipment to take excess boil off gas, cool it and re-introduce it to the tanks as a liquid, to prevent release to the atmosphere.
  2. Gas comes to the Cove Point facility via pipeline in a gaseous form. At the plant, it is re-liquified (this is the latest $4 billion investment they made), and then pumped via special cryogenic pipelines to the offshore terminal. These pipelines are double wall, with a vacuum between the walls (essentially a thermos bottle) to keep the LNG at -250*F. Again, permitting for this pipeline may be difficult, as it is not a "normal" gas pipeline. What makes LNG fuel economical in the US is its availability, hence low price. Since they have locked in delivery to Japan at a very high price, they would be loath to sell any product at going US prices.
  3. Yeah, since the Zoomies are always in air conditioning, they don't need different season uniforms.
  4. The Dominion Cove Point LNG terminal is an offshore terminal about 2 miles into the Bay. I am not sure the mooring arrangement could handle a cruise ship, even if they wanted to spend the time to divert there each trip. They could, however, contract with someone to build an LNG bunker barge, in the US, to run back and forth to the Baltimore cruise terminal. Without a lot of customers (only the one potential cruise ship), that would be a costly business for the cruise lines, as they would essentially be subsidizing the bunker company. Also, I don't know the Maryland or Virginia laws regarding loading and unloading LNG in metropolitan areas, so there could be some legal delays. And, the LNG export facility has only started about a year ago, and the export capacity has been sold to an Indian energy company for the next 20 years, and is scheduled to go to Japan, so I doubt they would look to provide the small amounts that one cruise ship would take.
  5. Again, UK uniform regulations are different, and I'm assuming the DW is still serving (hence the recent award). Just wanted to say that in the US, contrary to a lot of practice I see on cruise ships, that wearing uniforms by retired personnel is prohibited unless the occasion is related to the person's service. So, this is why miniature medals are allowed on civilian attire in the US.
  6. Unfortunately, another idea of yours that won't work, this time from a legal standpoint. One of the legal challenges when NCL bought the ship was from historical groups (not sure if the conservancy was part) to preserve the power plant, as this is the historically significant part of the ship. The power plant still remains onboard. And, as Crystal found out, in order to meet the new SOLAS requirements, you would essentially have to remove the entire stern of the ship and redesign for twin rudders, redesign the entire superstructure at a cost of hundreds of millions of dollars, and that is before any experimental work is done. The thought of the shielding required for a nuclear reactor on a passenger vessel is mind boggling, as is the liability to endless future lawsuits long after the ship is scrapped from anyone who sailed on the ship and developed cancer at any future time. As for using the SSUS as a test bed, one thing most folks don't know about is that a US flag vessel, when it does any repairs (or in this case total reconstruction and retrofitting power plants multiple times as they experiment) in a foreign country, the US slaps a 50% customs duty on the cost of all repairs and work. So, you would be limiting the total reconstruction of the hotel, and the cost of all the costly experimental power systems to being done at the much higher priced US shipyards (very few capable or desiring of doing this kind of work) or paying enormous duties to the US. While I agree that Carnival Corp has worn out its welcome as a good member of the maritime industry, I would like them to focus more on the types of environmental issues (garbage, plastics, sewage, ballast water, refrigerants, and sulfur emissions) than in a far more costly attempt to reduce greenhouse gases. Cruise ships account for about 5% of the world's ocean going tonnage, so trying to single them out for reducing fuel consumption is not going to help the planet much. 90% of the world's commerce travels by sea, so this is where the focus should be, and folks should brace for impacts on their life styles if this is where they want to go. The experimenting with new power systems needs to start with the lower power demand cargo ships, and then, just like with diesel electric, gas turbines, and azipods, it can be seen if scaling up for cruise ships is feasible for a proven smaller installation.
  7. LNG tankers have been transporting millions of tons of LNG, and burning it as fuel as well for decades, and there has never been a fire or incident. LNG is no more dangerous fuel than diesel or residual fuel, it just requires different handling and more treatment equipment. LNG, when not pressurized, is not explosive. Ship's LNG tanks are not pressurized like your barbeque tanks or buses, but are maintained at very low pressure and the excess pressure is what is used to fuel the ship. The ship relies on cryogenics rather than pressure to keep the LNG a liquid, maintaining the tanks at -250*F.
  8. The "LNG hybrid" for Princess is no different from the AIDA NOVA or any other marine LNG fueled diesel powered ship. Burning straight LNG requires a spark ignition (auto-ignition temp for natural gas is 750*C), while diesel fuel auto-ignites (the principal of a diesel engine) at 210*C and residual fuel at 400*C. So, on land, buses use spark plugs to ignite the LNG fuel, while marine diesels use 5% diesel fuel injected along with the LNG to "start the ignition along". This ability to inject gaseous and liquid fuels at the same time, make these "dual fuel" engines. They can operate on blends from 95% LNG/5% diesel to 0% LNG and 100% diesel (and residual fuel rather than diesel). AIDA NOVA can operate completely on LNG (well, 95%), but not sure if she does, as the LNG bunkering infrastructure is still not as developed as cruise lines would like. Further, the IMO's Safe Return to Port requirements of SOLAS require a second fuel for LNG powered passenger vessels, so there will always be a reserve of diesel fuel onboard.
  9. Sadly, most of these things are just not feasible for a cruise ship. The largest Flettner sails generate about 3Mw of propulsion, so you would need 15-25 of these sails to power a cruise ship (just the propulsion). Think what that would look like. The power savings is also dependent on wind speed and direction relative to ship's course, so you would still need diesels to operate when conditions are not optimal. When these things are proposed for ships, you have to realize that a cargo ship will have a hotel load of 0.3-0.5Mw (about 20-25 souls onboard), compared to a cruise ship's 8-10Mw. Also, while the largest container ships have propulsion engines as large or larger than the propulsion of a large cruise ship, most cargo ships run in around 20-30Mw of propulsion, compared to a cruise ship's 40-80Mw of propulsion power. As for solar panels, you'll notice that the entire area of hatch covers is covered in solar panels, for a small cargo ship. RCI tried solar panels on one of the Oasis class, and found that a large array could only provide power to the Boardwalk area. Solar power generation is a low density system (low wattage per area), while cruise ships are extremely dense power consumers. The entire sides and top of a cruise ship would need to be covered with solar panels and Flettner sails to power the ship, and you would still need to have azipods or propellers for when the wind isn't right, or when you are maneuvering into port, as well as battery banks and inverters for the solar panels. And, biofuels have their own set of problems, which is why no one currently runs more than a 20% blend of bio to fossil diesel. Sorry, while I see Samuel Cunard as a great businessman, who embraced new technology, I don't see much that makes him a "visionary" in the maritime world, as screw propellers were around for 20 years before Cunard used them, and iron ships were almost as old, and these are touted as some of his innovations.
  10. I'm not a lawyer, nor do I play one on TV, but I know that this falls under the Death on High Seas Act (DOHSA) in the US, and this limits compensation to only what the immediate family would lose of the decedent's potential income. Not damages, or expenses incurred by the family. Non-pecuniary damages (pain and suffering) are explicity disallowed. But the lawyers know this and will make the claims anyway. His severe heart condition would be taken into consideration when calculating his potential lifetime earnings.
  11. As stated before, you have heard one side of a legal argument. Lets wait and see what comes out in court before we cast aspersions on either Carnival, the Captain, or the ship's doctor.
  12. Just know that "medical evacuation insurance" does not cover an aerial evacuation from the ship. It only covers getting you from a medical facility where you've been disembarked to your home hospital. As for the lawsuit, there are a lot of things in it that don't make any sense, like "we can't evacuate you, because someone else is first"? I don't believe this for a second. My personal feeling is that when the people were informed of the cost of a medical flight to the US, they decided to remain on the ship, and when things went south, they decided to sue. JMHO.
  13. Whether its a "standard" tetrapak or this "biodegradable" one, my bet is it ends up in the incinerator onboard.
  14. OP, did you contact the port administration itself? Particularly in Italy, probably not likely to get an answer. Ask the cruise line for the contact information for their port agent in Naples, and contact them for any cost information and details of what you have to do. They can also set up ground transportation, for a fee.
  15. A fun fact I found a couple of days ago, when refreshing my mind on this topic for a Celebrity thread. And, by the way, Ms. Williams was announced as being promoted to Captain at Celebrity, but Virgin obviously gave her a better offer. Anyway, the fun fact is that, percentage wise, there are as many female cruise ship Captains as there are female airline Captains, around 3%. That represents 9 ship and about 4000 airline Captains. And the glass ceiling was broken 30 years ago, when the first female Captain was promoted on an ocean-going vessel. Everyone makes a big deal about cruise ship Captains because of the visibility of the industry, but if it were not for the true pioneers who started their maritime careers back in the 70's and 80's, these women most likely wouldn't be where they are today. Those women fought the stigma, the discrimination, and the infrastructure to allow women into the previously all male arena of maritime officers.
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