Let’s not talk about nuclear ships

You need a degree in physics to understand the subject of nuclear-powered ships. The technical issues that come with nuclear power at sea are not easy for an amateur, such as a generalist manager, to understand, and unless you can chat about why Hyman Rickover didn’t want liquid salt cooled reactors in 1952, why the positive void coefficient in an RBMK is so large, and how you can get nuclear weapons out of a thorium reactor despite the modern myth to the contrary, you don’t begin to understand which projects are feasible and which are selling snake oil.

The legal issues that come with a nuclear-powered merchant ship operating with cargo on international voyages are not hard to understand, but they are very annoying. Nation states have generally harmonised their laws relating to ships through the IMO, but they haven’t seen any reason to harmonise their laws relating to nuclear reactors through the International Atomic Energy Agency (IAEA), so when a nuclear reactor built and operating according to the laws and regulations of Country A finds itself in Country B, as often happens with ships, we have a bit of a problem.

The crew of a nuclear ship are going to have to be well paid, and well looked after

I’m not going to talk about either of those things. I’ll stick to something that we all understand – the crew. Nuclear-powered ships are a good idea for two reasons. We all know that they do not emit greenhouse gases, do not depend on the sun or the wind, can go for years without refuelling and can be of high power, i.e., fast. The other reason is that they will do more than anything else to improve the status, pay, and conditions of the seafarer.

People are going to be about as keen on the unmanned nuclear merchant ship as they are on the unmanned civil airliner. We want a nuclear ship to be carefully designed and built, to be carefully maintained, to operate under well proven procedures and to have a very good crew. Which means that the crew of a nuclear ship are going to have to be well paid, and well looked after.

Which leads me to the real problem with the nuclear-powered merchant ship. She needs a Reactor Officer. Reactor Officers are scarce, and the laws of supply and demand mean that they do not come cheap. They take years to learn their trade, starting – starting, mind – with that physics degree. And the nuclear navies – be they Russian, Chinese, American, French, Indian or British – hang on to their Reactor Officers, for fear that they might decide that running a power station and getting home to see the family every day beats going to sea, and word reaches me that in some of those nuclear navies, Reactor Officers are lured back to sea on film star wages until they are into their sixties.

You won’t be surprised to know that one of the operational issues with the USS Savannah was that her deck officers thought they ought to be on the same film star wages as their reactor officers, and went on strike…

Unlike fuel cells, which have been the Next Big Thing for decades, or ammonia, or sailing ships, which we used to know about, but have forgotten, nuclear power is a very well understood technology of the present day. It’s safe; it has killed fewer people per tera-kilowatt-hour than any other source of motive power, but if we are going to use it to help to get merchant shipping away from the oxidation of fossil hydrocarbons, we need to scale up our recruitment and training. In place of a couple of hundred submarines and less than two dozen aircraft carriers and icebreakers, owned by governments, we are going to need to man some thousands of ships, even if we confine the use of nuclear power – as we probably may – to large ships on long hauls, and as noted above we are going to need rather good people.

Nuclear ships are not silly, and they need not be dangerous. The public will accept them in the end, as will the ports and the Suez and Panama Canals, although they say they won’t. The problems are getting the first cost down to something more affordable (and let us remember that quite a few serious people, like Lloyds’ Register, are working on civil marine reactors) and finding and educating, as well as training, the crews. The real winners are going to be the crews. And that is a good thing.

Andrew Craig-Bennett

Andrew Craig-Bennett works for a well known Asian shipowner. Previous employers include Wallem, China Navigation, Charles Taylor Consulting and Swire Pacific Offshore. Andrew was also a columnist for Lloyd's List for a decade.


  1. just a quick line to talk about decommissioning costs and the staffing required to do it

    1. Decommissioning must be guaranteed, and must be paid for in advance, as part of the initial financing package. There are ways in which this can be done. It’s a part of the financial engineering that nuclear powered ships – which save perhaps half of the thirty year lifetime cost of a diesel installation, but which require all the fuel bill to be paid for in advance – will involve.

    2. + Vessel accidents, i.e. cargo fires, collisions, sinking. What’s potential for environmental damage from one reactor failure due to these causes?
      + Piracy? If the operational paradigm changes to quasi-military, is there any ROI scenario that makes sense?

      It seems to me the whole life-cycle and safety processes of vessels has to be reconsidered. I’m just thinking out loud and don’t have any background in these areas but would like to see these explored. I think this is an important topic.

    3. Gareth, please checkout Molten salt reactors, you will be pleasantly surprised, it is your duty.

    4. Hum

      In the city where I live the naval dockyard has a dock with a number of retired nuclear powered vessels. xSome have been there for 20 years. That they have not been decomissioned is not due to a lack of will or finances. It is due to the fact that no one knows how to do it safely. As for cost, unkown but certainly in the hundreds of millons each.

      There is a lot of private capital flowwing into “compact nuclear” and many unproven claims about safety and cost. As for building in decomissioning costs to the purchase price, that is simply nonsense, there are no examples of an approach to do this let alone practical examples to base the cost/risk calculations on.

      I seriously doubt this site will publish this comment but some things should be stated.

      1. The West German nuclear ore carrier “Otto Hahn” had her reactor decommissioned and has since been first converted into a containership and then scrapped. The Japanese nuclear ship “Mutsu” has had her reactor removed and is still operating as the oceanographic research ship “Mirai”.

  2. Very well presented essay regarding the benefits of nuclear power. Thanks very much!!

  3. With rising temperatures and we all start sizzling in the heat, I am sure that this will be the catalyst when the public will accept the nuclear option for ocean transportation…..

    Molten Salt Reactors (m-MSR), in certain configurations, can consume over 95% of its fuel, as opposed to 1% for pressurized water reactors. Even after the m-MSR is decommissioned, the fuel can be reused in follow-on reactors.

    The Marine Molten Salt Reactor Information Pack by Core-Power makes very interesting reading.

    1. CorePower has made a lot of noise about their alliance with TerraPower, but a closer examination shows that TerraPower had never said a thing about putting their molten-chloride fast reactor design on a ship. Nor have they claimed fuel efficiencies anywhere near what you and CorePower are claiming. Indeed, in recent testimony to the National Academy of Sciences they admitted that their fuel consumption efficiencies will be very much on the order of today’s pressurized water reactors, about one-half of one percent efficient use of the original mined uranium that ultimately makes up the fuel. Nothing to get excited about.

  4. Thanks Andrew, for a clearly written article, which cuts out much of the background noise on this subject and focuses on the practical issues.

  5. Weather dependent fuel saving devices are not making an impact. Not on land and not at sea. Advanced atomic propulsion is the only actual zero-emission system that can power ocean transportation and create a new competitive advantage for our industry. It can create interesting and rewarding careers for a new generation of graduates in high quality, high income environments at sea, and why should we not want that? The headline hints at this and could be completed by saying “Let’s not talk about nuclear ships, let’s talk about a new generation of expert seafarers.’ Travel the world and meet interesting people.

  6. The engineers on the NS Savannah were not paid rock star wages. The original engineers were MEBA District 1 and the Mates were MMP
    They were all fired and replaced by The Brotherhood of Marine Officers BMO which represented both the Deck and Engine Officers. They worked for lower wages than the original crew. They did not have degrees in Physics. There was a Chemist on each watch in the engine room.
    Engineers on US Flag Passenger ships made higher wages and better benefits

  7. I couldn’t read too far into the article if the author can’t even get the ships name right. It’s N.S. Savannah (Nuclear Ship) not U.S.S. Savannah, which denotes a navy ship.

  8. What a self fulfilling piece and so obviously written with little thought. What a foolish idea. Do you have any idea how many ships sink, crash, burn? Oh yeah…great idea to have radioactive shit further contaminating our oceans. This is a poorly thought out dream and it needs to remain a dream. BTW there still is no good way of addressing the waste produced by nuclear reactors. Get with the reality program Bub.

    1. There is no problem with nuclear “waste”. There is very little of it; it is contained unlike combustion gasses; it is almost entirely solid; it can be reprocessed and the fission residue decays away in a couple hundred years to be no more active than natural ores (unlike arsenic and other hazardous chemicals that don’t decay at all); it has not caused a significant accident in 60 years; there are well developed technologies for vitrifying and burying it. Its only problem is an unearned reputation perpetuated by those who have not understood the simple facts (including Mark, it seems, and some interested parties, no doubt)

  9. Thank you for your thoughtful comments. After forty five years in merchant shipping, I do indeed “have an idea how many ships sink, crash, burn”, as you put it.

    I am sure your well thought through observations will persuade many people that it is better to carry on polluting our oceans and our atmosphere by burning fuel oil.

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