I saw that a new giant cruise ship powered by methane gas has just entered service. The linked article talks only about the risk for climate change which might be caused by leaking gas, but I thought that it overlooks a much bigger risk. Methane is a lot more volatile and it is a lot more explosive than other fuels (Except hydrogen of course). I checked the technical details of the ship on Wikipedia and I saw that her generators at full power could provide almost 90MegaWatts and just for moving at full speed it might need up to 60MW.

I did a rough calculation. Assuming an average consumption of 50MW in one day it would consume 1.2GW*hour. Since it is not easy to find a fuelling station for a ship of this kind I assume that it will need to store fuel for at least 8/9 days of continuous operation which is more than 10GW and I guess this is a very conservative estimate.

According to this site 10GW*hour are equivalent to the destructive power of more than 8 Kilotons. Trouble is that this is not a gas storage facility kept at a safe distance from people. Counting passengers and crew at full load there could be almost ten thousands people sitting on that destructive power. So I am wondering through what kind of risk assessment the ship went through in order to be allowed to operate. What are the relevant international regulations on the subject?


Judging from the current answer, the comments and the votes it seems that my question is not clear. I'll try to explain it with different words.

Until now we had and we still have many small vehicles powered by gas on the public roads, but each with a limited quantity of gas. Then we had ships transporting LNG in enormous quantities with small specialised crews and far from other people. We also have storage facilities holding big quantities of gas with few specialised personnel, far from the other people.

This ship is the one of the first few instances where we put together big quantities of gas and ten thousand people in the same confined space. For the moment it is a rare case, but it is going to become a trend. I assume that from the engineering point of view it was designed with special requirements, but I wondered if there are also special legal requirements. My question is not whether they can or cannot enter a port. My question is how the construction and the beginning of the operations of this kind of ships is approved in the first place.

  • 2
    Your calculation is totally ignoring that fuel oil contains more energy per volume.
    – Trish
    Jan 28 at 12:58
  • @Trish i wanted to be conservative therefore I ignored the efficiency losses, I know, but the numbers are already scary when they are so conservative.
    – FluidCode
    Jan 28 at 13:01
  • 1
    That's not what I tried to say. I mean, that the energy contained in the oil bunkers of a typical cruise ship is larger than in the gas tanks of a methane ship.
    – Trish
    Jan 28 at 13:03
  • 2
    In order for that methane (or any similar fuel) to produce the kind of "explosion power" you quote, it would need to be homogenously mixed with an ideal ratio of air (or other oxygen source) to support near instantaneous combustion of the entire volume. You're looking at it as if it's a "thermobaric bomb" when in practice it would be very difficult (if not outright impossible) for the methane fueling a cruise ship to behave that way.
    – brhans
    Jan 29 at 14:47
  • 1
    Your assessment that storage facilities are far away from people is wrong. Natural Gas Storage often was right inside cities for a long time. While nowadays many Gasometers have been converted to other uses, that was not because of danger but because the gas net was made better.
    – Trish
    Jan 30 at 17:46

1 Answer 1


LNG has been used as a fuel source safely for many decades

It is a common fuel for trucks and busses and has been transported by ships carrying far, far more than would be needed for propulsion. LNG carrier with 135,000 m2 capacity

LNG carrier with 135,000 m2 capacity

The first LNG powered ship entered service in 2018 and more than 20 have done so or have been planned since then.

All international shipping (except warships even though most of those do anyway) must comply with the SOLAS Convention if it is to enter the territorial waters or ports of any of its 167 contracting states. There is no reason to think this one doesn’t.

  • Comments have been moved to chat; please do not continue the discussion here. Before posting a comment below this one, please review the purposes of comments. Comments that do not request clarification or suggest improvements usually belong as an answer, on Law Meta, or in Law Chat. Comments continuing discussion may be removed.
    – Dale M
    Jan 29 at 21:52
  • 3
    @MichaelHall all non-warships are merchant ships if over 500 tons. A ship is also a passenger ship if it carries more than 12 passengers SOLAS contains additional requirements for those as it does for tankers etc.
    – Dale M
    Jan 30 at 6:23

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