Page 154 - ΝΑΥΤΙΚΑ ΧΡΟΝΙΚΑ - SEPT 2025

Feature

Nuclear propulsion is “silently” supported by the tion (this is a low risk) should be provided.
US Administration and several US companies; However, any leak from a molten salt
yet, it has not been discussed in detail during reactor will lower the fuel's temperature,
any of the IMO meetings so far. It seems likely which will solidify, and the chain reaction
that the new Trump rhetoric will contribute to will be stopped at temperatures below
changing the public sentiment in favour of nuclear 450°C. Since the “Savannah”, the first
propulsion. nuclear-powered ship, was built in 1962
as an ambassador for the peaceful use
of nuclear power, three more nuclear-
powered ships have been built. One in
France, one in Japan, which never oper-
ated commercially, and one more general
cargo ship in Russia that utilised the same
type of reactor as the ice-breakers. The
latter is still in use in the Russian Arctic
region.

fuel, and the fact that online reprocess- What are your thoughts on floating
ing systems produce mixtures that are nuclear power plants (FNPPs) as
difficult to purify and reuse. a potential shore power solution
for energy-intensive ports or ship-
What types of ships or operational profiles yards?
(e.g., tankers, LNG carriers, bulkers, Another area for expanding the small
containerships) would you consider reactors nuclear technology is the instal-
most suitable for nuclear propulsion lation on floating barges positioned away
in the first wave of adoption? from the jurisdiction borders of devel-
Technically, nuclear reactors can be used oped countries. The cost of cooling water
on all types of ships, keeping in mind that will be minimal, and many legal issues,
the higher the required power, the more permits, and other requirements will be
economically feasible the use of a reactor easier to handle. Security measures will
will be. Operators can increase the speed be easier to implement. Such reactors
of their ships without fearing that their can be used to provide electrical power
emissions will increase and that they will ashore, produce hydrogen and ammonia,
be financially penalised. Some designs or other environmentally friendly fuels.
place the reactors in the engine room Several countries, both in the Atlantic
area, while others in the middle of the ship. and in the Mediterranean, are studying
Major overhauls will be planned at five- this option, and at least one of them has
year intervals, and reactor refurbishment/ issued preliminary tender documents.
replacement/re-fuelling every 20 or 25 With reference to providing electrical
years. One of the critical issues that SMR power ashore, it is worth noting that at
reactor technology should address is the present, there are at least 75 floating sta-
slow response to load changes in the tions utilising liquid fuels or LNG, provid-
reactors. That can be solved by charging ing power to many areas, mainly in under-
battery banks or steam dumping, if nec- developed countries. A case in point is
essary, or by installing separate, small Iraq, which recently commissioned
propulsion units for entering or leaving two floating power stations providing
port, which may render the propulsion 600 MW of electricity to Basrah.
system non-100% carbon-free. Whilst in Russia has a PWR installed on a floating
port and in order not to shut down the structure, which has been in operation
reactor, the ships can provide electrical since 2020, with no significant problems
power to the shore grid. During sailing reported, despite the reactor being of an
in the open sea, steam turbines or elec- older technology. Recently, Terrapower,
tric propulsion can be utilised. The reac- a Bill Gates-associated company, entered
tor should be installed at the centerline into an agreement with HD Hyundai
of ships with sufficient double bottom to develop and test marine-type nuclear
protection to minimise any risk of flood- reactors. This trend is expected to con-
ing. Measures to protect against radia- tinue growing.

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