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  1. If the Chinese want nuclear powered cargo ships, they will have them. They also have the stones to leverage access to their market to give those ships access to foreign ports.
    Also if they needed half a million operators, they would select them at twelve years of age and have them ready to stand reactor watch at twenty. Its not like they lack a pool of potential candidates.

  2. DV82XL – if the US wanted a pool of operators, it would also be simple to go out and recruit a bunch of highly motivated middle school students by guaranteeing them a college education if they meet certain standards.
    All you have to do to believe the truth of that is serve for a period of time on the board of a competitive sports team to learn just how dedicated both athletes and parents can be to an endeavor with the potential for payback with a full ride scholarship.

  3. The real competitive advantage of nuclear powered shipping is the cheap fuel. Since fuel is cheap, I would assume that nuclear powered shipping would not move at a leisurely 15kts like its conventional competitition. It would be running flat out port to port at hull speed. If it is hauling a high value cargo such as crude oil it can cut the shipping time in half and save a bundle of money for the owners of the cargo.
    Hull speed is related to the length of the ship (proportional to the sq rt). The Emma Maesk is is the biggest and longest container ship in service. It has a top speed of 25kts but normally cruises at 16kts to improve mileage. Presumably, the EM top speed is limited by the engine size. The Emma Maesk is longer than the US aircraft carriers which routinely run in excess of 30kts.
    Bill

    1. Bill Young wrote:
      The real competitive advantage of nuclear powered shipping is the cheap fuel. Since fuel is cheap, I would assume that nuclear powered shipping would not move at a leisurely 15kts like its conventional competitition. It would be running flat out port to port at hull speed. If it is hauling a high value cargo such as crude oil it can cut the shipping time in half and save a bundle of money for the owners of the cargo.
      Not only for high value cargo. The fact that the ship gets to its destination faster means more turn-arounds per year, which also makes the ship and its personel more valuable.
      Nuclear power has the potential to be a game changer. It reminds me of when jet aircraft came in. They became the workhorses they are not because they were more fuel efficent compared to the prop aircraft, but because they got their destinations so much sooner. This allowed the the same plane and crew to make more flights each day, which more than paid for the additional fuel costs.

    1. Yes, the pirates are still operating. There is strong evidence showing that high speed vessels are much safer and able to prevent boardings. Based on the reports I have seen none of the captured ships were going faster than 20 knots.
      Nuclear powered ships would use high speed as one of their primary economic advantages as well as a self protection measure.

    2. The few mentions of speed of Somali pirates that I can find from a brief Google search indicate speeds of up to 23.5 kt vs. a ship operating at 22 kt.
      I do know that internal combustion engines operated at over their “sweet spot” in terms of RPM tend to exhibit large decreases in efficiency. So, I can imagine that unless the Somali pirates are using purpose-built speedboats, their sprint speed might be unable to be sustained for long unless they want to be towed back to their “mothership” for want of fuel.
      I’m going to guess – somewhat uneducatedly – that unless the pirates start the engagement from a near-perfectly favorable position (e.g. their course is in the direction of the target, and the target’s course is in their direction; target’s bearing is 90, pirate’s bearing is 270) the chance they have of closing sufficiently to be able to board a ship designed to run at high speeds for a very long duration is not that great, and it would require varying their course in a precise window of time at a precise rate unless they were able to go much faster than the target ship. But this is all somewhat un-educated guessing.
      One question: setting aside fuel efficiency (and crew comfort), are there other considerations aside from engine power that dictate the maximum speed of a surface vessel? Propeller damage due to cavitation? Yaw or pitch stability problems?

      1. Dave,
        Virtually all cargo ships have displacement hulls (they push water out of the way rather than ride on top like a speedboat). Displacement boats have a maximum speed called the hull speed. The rule of thumb is that the hull speed (in knots) = 1.34 x square root of the length of the water line in feet.
        The water line is the length of water contact from the bow to the stern and is longer than just the length of the boat in the water. The overall length of the boat is a fair approximation. My 25 foot sailboat has a hull speed of about 5 knots. The USS Enterprise at 1100 feet has a hull speed in excess of 33 knots.
        Bill

        1. Bill – good explanation. It is also worth mentioning that the power required to push displacement hulls through the water is proportion to the cube of speed. The difference in total energy consumption between a speed of 15 kts and 30 kts is a factor of 4 because the ship should get there in half the time.

          1. Thanks, Bill and Rod. So it’s more of a “brute force” sort of thing, needing to force the water out of the way. I did a bit of reading on the topic on WP; I can imagine that you couldn’t fool with the displacement hull of a cargo ship much, though it did mention that a bulbous bow design might provide some additional efficiency.
            I also once read a science fiction book that had the idea of using compressed air so as to create a sort of bubble-filled medium around the displacement hull of a ship to reduce drag on it by lowering the density, kind of like the Shkval (http://en.wikipedia.org/wiki/Shkval) supercavitating torpedo uses a part of its own exhaust gasses to do (although the Shkval is, of course, intended to stay underwater for the duration of its short mission). An interesting concept, if I say so myself.

            1. @Dave – so what is wrong with a “brute force” method of propulsion when you have lots of inexpensive brute force at your disposal and your potential competitors do not?
              As Bill mentioned earlier, the real advantage for nuclear energy comes in the form of really cheap and long lasting fuel. Not only are the BTUs available at about 1/20th the cost of BTUs from diesel fuel, but the hull displacement volume taken up by fuel is tiny and unchanging. For a large commercial ship operating at a reasonable speed over a long transit route, as much as 30% of the hull volume is not carrying cargo, but carrying consumable fuel. As the ship burns through its fuel load, the operators have to take some action to keep the ship balanced. Up until a few years ago, it was quite common for fuel tanks to be self compensating. As the fuel burned, ballast water filled into the bottom of the tank. As you might imagine, getting rid of that fuel contaminated water at the destination is not simple, especially once people began to figure out all of the other “stuff” from distant waters it contained.
              The lack of ballast water systems, lack of atmospheric emissions, and the ability to put the fuel and power system in protected locations in the center of the ship are additional bennies that come along with the cheap, long lasting fuel. For me, this is a no brainer application that really needs to be pursued with due haste. About 6% of the 80 million barrels of oil per day that the world economy burns gets burned on commercial ships that could be nuclear powered.

              1. There’s nothing wrong with brute force. (I was just going off on a tangent, something I do once in a while…the subject of how there is some sort of real “speed limit” for ships in water piqued my technical interest, as I had never really thought of that before. Fluid dynamics is such an interesting field.)
                I concur with everything that you said regarding the unique potential of nuclear power aboard cargo ships. Of all the things that nuclear does well, it has uniquely high potentials for utterly game-changing performance in isolated systems like ships, submarines, spacecraft, remote or isolated communities, or Antarctic bases, for the simple reason of being self-contained, the incredible energy density that it brings to the game, and a presumably far higher degree of ultimate reliability, with fewer moving parts and fewer linkages between those parts, than something like a diesel engine. These factors will inevitably result in a far lower total cost of ownership.
                For something like a cargo ship, it’s an extremely logical choice, one that should be pursued immediately, especially in the context of the need to reduce transportation costs, reduce dependency on foreign oil, and clean up ship emissions, of both the liquid and the gas types.

                1. Dave,
                  To feed your tangent, the ‘speed limit’ applies to displacement hulls, not speed boats. When you are going slowly in a displacement hull vessel, you will see 3, 4 or maybe 5 waves coming off from the front and sides of your boat. As you speed up, the number of waves goes down. As you approach your hull speed you will only have one and, as I understand it, at your hull speed, your boat will be 1/2 of a wave length long. Your bow (front) will be up against a wall of water and your stern (back end) will be in the trough of the wave. As I understand it (and hydrodynamics is not my field) at this point to go any faster the boat would have to start planing (i.e. come up out of the water like a speedboat).
                  Happy sailing,
                  Bill

          2. Indeed, as Rod Adams says up there at 6:26 AM, power (RATE of energy consuption) is proportional to speed cubed. I was always amazed by that fact.
            A third way to look at it is this: The USN’s CGNs had dual complete engine rooms (most of them anyway– can’t vouch for CGN-9). We could run at the published speed of 31+ knots at full power, but let’s say 31 knots. Then we could run 25 knots on just one “cross-connected” plant– six knots cost half the power.
            Of course, that is neglecting the plants’ support needs like pumps and such, plus the “hotel” needs of the ship like, you know, fire control and radar and viscocity. At some speed, the function will flip and you’d be going too slow.
            How does this translate for compressible non-viscous fluid? You’d have to ask, say, Neptus Lex, about how this translates to cars and planes. I’m pretty sure doubling your speed in air doesn’t take eight times the power. And with liquids, viscocity creaps in when pumping thick oil.

  4. Uranium production is already less than the annual civilian requirements. The additional fuel requirement would require shift to recycling and fast reactors. Something like the revised Hyperion design featuring a fast reactor. Only the Chinese can dare to put it into bulk production.

    1. @jcdhall – (btw, it is probably not a good idea to use your email address as your comment name)
      Uranium production is less than annual civilian requirements because there is a large quantity of inventory being sold off by the owners of that inventory. That is keeping the price of uranium down and limiting the production to keep the overall sales in balance with the available material. Wouldn’t it be great if the properties of oil, coal and gas were such that we could store many years worth of inventory?
      That aside, why do you think that only the Chinese would dare to put fast spectrum reactors into production? What about the Russians, Indians, French, and Japanese. How about Americans; do you think we have lost our technical competence?

    1. Well I was trying to watch it DocForesight but my wife said I needed to get my work done. All I can say is that it is old technology so it must not work as well as this fancy new stuff. These are obviously doctored photos. I bet they are even using depleted uranium…. horrible!!

      1. Obviously “doctored” photos. LOL I resemble that remark. Reminds me of one of Jackson Browne’s greatest hits “Doctor My Eyes”. Gotta love YouTube for the service they provide.

  5. Rod Adams wrote:
    On the other hand, Intertanko? website reveals a possible source of antinuclear bias. Tankers ensure that ?he oil that keeps the world turning is shipped safely, responsibly and competitively,?it points out. Clearly the group looks to the trade and transport of fossil fuel for its bread and butter?nd may be reluctant to switch to a different power source.
    For as much as those in the oil business like “making” oil, they like making money even better. If nuclear powered tankers became more economical than oil powered tankers, I am certain you would see the industry switch for their new tankers.
    There is growing international pressure to require low sulphur (distillate) fuel for ocean-going ships. This fuel is more expensive, which makes the nuclear option more attractive.

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