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cost of a nuclear-powered ship (CaPex +
OpEx for the five-year cycle maintenance
of the reactors + fuel) may give shipown-
ers a competitive advantage if the cost
of fossil and zero-carbon fuels, which are
both expected to increase, is calculated
over the useful lives of the ship.

To what extent are flag states and port
authorities prepared to handle
nuclear-powered ships?
At the moment, commercial nuclear
ships cannot enter ports without special
permission. The IMO developed the Con-
vention on Nuclear Ships in the 1960s,
but its efforts were abandoned, possi-
bly due to the effects of the Cold War
period. Today, this convention should
be re-discussed and a new, updated
convention finalised, possibly with the
help of the International Atomic Energy
Agency, which is supporting this effort.
That would enable flag states and port
authorities to accommodate nuclear The NS (Nuclear Ship) "Savannah", the first commercial nuclear power cargo vessel,
ships without compromising the safety en route to the World's Fair in Seattle.
of the local population. Credit: Elton Lord/Atomic Energy Commission, Public domain, via Wikimedia Commons.
a nuclear-powered ship will also be more engineers will not be possible; therefore,
What are the major technical challenges difficult, if allowed at all. Reactors will the only solution will be for reactor man-
in integrating nuclear power into have to be delivered complete with their ufacturers to provide reactor operators.
commercial vessels? casings, and any potential need for repair Reactors will produce steam, so it will be
Nuclear technology is unknown to and maintenance must be addressed necessary to educate the engine room on
shipbuilders, shipyards, and operators. from the design stage. The engine room steam or electric propulsion. In principle,
Nuclear reactors that may be used on space will need to be enlarged; however, the operation and maintenance of the
merchant ships may also be used for devices such as exhaust gas cleaning auxiliary systems of a nuclear ship may be
navy ships, creating the need for strict systems or carbon capture and storage simpler than the new technology systems
controls on who is to produce and who is systems will not be required. Training that may have to be installed on ships
to install them on board ships. The sale of engineers to become nuclear reactor utilising other zero-carbon fuels.

Are there concerns regarding radioac-
tive waste management at sea?
There are two more issues to discuss: the
recycling of the reactors' used nuclear
fuel and its possible use for the man-
ufacturing of weapons. MSR reactors
utilise their fuel down to almost 99%
in comparison to the PWRs, which only
utilise 5% to 10%. The fuel from an MSR
can often be reprocessed and reused in
the same or a similar reactor, either in
batches or by removing all the fuel and
enriching it for reuse. It has to be noted
here that some MSRs operate like PWRs
and would still produce radioactive waste
that should be stored. The practical bur-
dens of reusing the MSR fuel for produc-
ing weapons-usable material are the high
radioactivity, the corrosiveness of the

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