Momentum Builds Behind Nuclear-Powered Shipping as Regulatory and Technical Efforts Accelerate

International Shipping News — 10/08/2026

The push toward nuclear-powered commercial shipping gained significant traction at Posidonia 2026, where Lloyd's Register (LR) convened senior leaders from the maritime and nuclear sectors for a high-level roundtable focused on the practical steps required to enable safe, commercially viable nuclear propulsion at sea. The growing interest in nuclear propulsion comes as the maritime sector faces mounting pressure to decarbonize, with international shipping accounting for approximately 3% of global anthropogenic CO2 emissions and the IMO targeting net-zero greenhouse gas emissions from international shipping by or around 2050 under its 2023 GHG Strategy.

Building an International Regulatory Framework

The roundtable assembled representatives from shipowners, reactor developers, regulators, and industry bodies to explore three themes central to the future of nuclear-powered commercial shipping: regulation, commercial viability, and technical implementation.

A dominant theme was the need for an international regulatory framework capable of evolving in step with technological advances, rather than waiting for mature reactor designs before establishing deployment rules.

Opening the discussion, Karine Herviou, Deputy Director General of the International Atomic Energy Agency (IAEA), underscored the importance of regulatory certainty as technologies continue to progress.

"This is a very important conversation," she said. "One of the main issues is the need to have an international framework to provide regulatory predictability."

The discussion also reinforced the importance of cross-industry collaboration, with participants recognising that progress will depend on regulators, technology developers, and operators working together from an early stage.

Reflecting on the event, LR CEO Nick Brown highlighted the pace at which reactor technology is advancing: "We heard of the very clear and compelling speed that the regulation needs to be here because we have small modular reactors starting to go critical within the next month."

Since the roundtable, that pace of development has been demonstrated by Deployable Energy, whose Unity demonstration reactor achieved criticality at Idaho National Laboratory in early July. Developed in just two years, the company has also secured orders to supply 500 units per year for data centre applications between 2030 and 2035. LR Advisory has supported the development of the Unity Nuclear Battery and continues to collaborate with Deployable Energy to explore the potential application of advanced microreactors in the maritime sector.

Brown added: "Today's conversation was a very clear indication that the work of Atomic Technologies Licensed for Applications at Sea (ATLAS), the work of the UK Maritime Nuclear Consortium, the work of NEMO, is going to be demanded by industry to ensure that there is a path to application and scale."

Commercial Realities and the ATLAS Initiative

Alongside regulation, participants examined the commercial realities of nuclear-powered ships, including investment models, operating economics, and the potential competitive advantages available to early adopters. While significant challenges remain, discussions reflected a growing willingness to explore how nuclear energy could complement other zero-carbon fuel pathways — such as ammonia, methanol, and hydrogen — each of which faces distinct hurdles in fuel availability, bunkering infrastructure, and onboard storage. Nuclear propulsion's appeal includes the potential to eliminate refuelling stops for years at a time, though it introduces novel challenges in crew training, liability frameworks, and public acceptance that no other fuel pathway entails.

Central to these discussions is the ATLAS initiative, which aims to establish a clear framework for the safe and secure deployment of civil nuclear technologies in maritime applications by addressing key regulatory, safety, and assurance challenges.

Progress is also being made at the International Maritime Organization (IMO). Speaking at the NEMO workshop earlier in August, the IMO announced that it expects a new nuclear code to be adopted in 2032 — four years earlier than previously anticipated — reflecting the growing pace of international regulatory work alongside advances in reactor technology.

Demonstrating Technical Feasibility

While regulatory frameworks are beginning to take shape, technical development is also accelerating. During Posidonia, LR announced a joint development project with Hyundai Heavy Industries, Korea Shipbuilding & Offshore Engineering (KSOE), Hyundai Glovis, G-Marine Service, and the Korea Atomic Energy Research Institute (KAERI) exploring the application of an advanced small modular reactor aboard a pure car and truck carrier (PCTC).

The project examines how a Molten Salt Reactor (MSR) could be integrated into a large vehicle carrier, assessing everything from reactor placement and shielding requirements to vessel stability, propulsion arrangements, and cargo capacity. MSR technology is of particular interest for maritime applications because molten salt designs operate at near-atmospheric pressure, potentially reducing the risk of pressure-related failures compared to conventional pressurised water reactors, though the technology remains less mature at a commercial scale.

Safety forms a central part of the work, with LR leading hazard identification and preliminary risk assessment activities to examine containment, onboard safety systems, and operational considerations associated with nuclear propulsion.

The project reached an important milestone with the award of an Approval in Principle (AiP), confirming that the concept is feasible at a preliminary design stage and establishing a foundation for further development.

Commenting on the project, Sung-Gu Park, President – North East Asia at LR, said: "While nuclear propulsion is still at an early stage of development, this project shows the importance of building technical understanding now to support future progress."

"Establishing feasibility at concept stage is a valuable step forward, particularly in areas such as cargo optimisation, vessel stability and integrated safety design," he added.

Concept studies represent an early phase of development and offer a glimpse into future nuclear technologies and how they could be integrated into commercial vessels, helping to identify the engineering, operational, and safety considerations that will shape future designs.

Preparing Ports for Nuclear Shipping

Work is also underway to understand how ports could support future nuclear-powered vessels. In June, LR, the Port of Rotterdam Authority, CORE POWER, and A.P. Moller – Maersk published a study exploring the requirements for nuclear-powered commercial ships to make routine port calls in Rotterdam.

The study considered emergency planning, regulatory responsibilities, port infrastructure, and stakeholder coordination, helping to identify the practical considerations associated with routine port calls by nuclear-powered merchant vessels. Port preparedness is widely regarded as one of the most complex enabling factors, as each jurisdiction a vessel calls at may impose distinct nuclear licensing, liability, and emergency response requirements.

Alongside initiatives such as ATLAS and concept vessel studies, this work reflects a broader shift toward considering the wider ecosystem needed to support commercial nuclear shipping — from regulation and vessel assurance through to port operations and infrastructure.

Source: Lloyd's Register