Page 173 - ΝΑΥΤΙΚΑ ΧΡΟΝΙΚΑ - SEPT 2025

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The IMO’s regulatory framework for (NTQs), and approvals in principle (AIPs).
nuclear merchant ships was introduced The SMR philosophy could impose
in 1981 through Resolution A.491(XII), restrictions on ship design. The modu-
a supplement to SOLAS Chapter VIII. larity concept imposes a fixed maximum
In June 2025, the 110 session of the power output per reactor, corresponding
th
IMO Maritime Safety Committee (MSC to a set lifespan of its core. Although it
110) prepared instructions for relevant is possible to operate an SMR at a lower
sub-committees to initiate the revision constant power level, its core will last
of the code and assigned this task to longer. This may cause the reactor’s
the Sub-Committee on Ship Design end-of-life to decouple from the ship’s
and Construction (SDC), requesting it to standard dry-docking schedule, thus
submit proposals for the revised version leading to significant additional oper-
of A.491(XII) in January 2026. ational costs. Hence, SMRs would be
The ratification or updating of the Brussels better suited for larger ships.
Convention and its implementation in Another technical issue to consider is
international law is likely to be needed nuclear power plants’ ability to toler-
to allow the insuring of SMRs before ate higher accelerations caused by ship
they can be commercially deployed. motions and vibrations, allowing for flex-
This will give significant momentum to ibility in the overall design. While there
further discussions on liability insurance, are significant safety benefits to placing
chartering, and finance matters. the plant amidships, this location may
not be feasible for specific vessel types
What are the major technical challenges like oil tankers and LNG carriers, or it
in integrating nuclear power into may negatively impact cargo capacity.
commercial vessels? Challenges related to access to suita-
Currently, ABS supports the industry ble shipyards or other support facilities,
through joint development projects as well as the physical removal of the
(JDPs), new technology qualifications reactors, are major concerns. The degree

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