ABS delves into potential of nuclear propulsion on LNG carrier

Classification society American Bureau of Shipping (ABS) has released a new report highlighting the potential of nuclear technology in the maritime industry through a study of a small modular reactor (SMR) on a standard LNG carrier.

The study modeled by ABS and Herbert Engineering Corporation (HEC) looks into the transformational impact of a high-temperature, gas-cooled reactor (HTGR) on the design, operation, and emissions of a 145,000 cubic meter (cbm) LNG carrier design.

Designed to help the industry gain better insight into the feasibility and safety implications of nuclear propulsion and to support future development projects, the study aims to provide information on heat and energy management, shielding, weight distribution, and other design features for an LNG carrier with nuclear propulsion.

Identifying design issues that will inform future rules development was also one of the goals of this study.

According to ABS, the study found that the HTGR technology allowed faster transit speeds and offered zero-emission operations without the requirement to refuel. However, the HTGR technology would need replacing approximately every six years.

It showed that a nuclear-propelled LNG carrier would have specific design features, with reactors placed at the rear of the vessel and batteries forward of the location occupied by fuel tanks on current vessels and a reinforced hull. Given design constraints, the HTGR technology would only be suitable for larger LNG carriers, ABS explained.

“While this technology is well understood on land, adapting it for marine application is in its infancy. However, this study and the other research we have carried out clearly highlight its significant potential to address not only shipping’s emissions challenge but to deliver a range of other operational advantages to the industry. ABS is committed to helping the industry evaluate its suitability for use in a range of use cases and LNG carriers is just one of a range of potential applications we are exploring,” said Patrick Ryan, ABS Senior Vice President and Chief Technology Officer.

Earlier this month, ABS launched what is said to be the industry’s first comprehensive rules for floating nuclear power plants at a forum for nuclear industry leaders held jointly with Idaho National Laboratory (INL) at ABS’ headquarters in Texas.

Together with HEC, the classification society also published a detailed study modeling the design, operation, and emissions of a floating nuclear power plant.

In 2023, HEC and ABS presented a study on nuclear propulsion’s impact on the design, operation, and emission profile of two ship types, a 14,000 TEU container vessel, and a 157,000 DWT Suezmax tanker.

This study found that the adoption of advanced nuclear reactors onboard a 14,000 TEU containership would basically eliminate the need for refueling of the vessel during its entire 25-year lifespan.

On the Suezmax vessel, the study found the addition of four, 5MW, heat-pipe microreactors, while decreasing cargo capacity, would raise operational speeds and only require refueling once during its 25-year life. Both concept vessels would emit zero CO2.

ABS’ other endeavors in the nuclear propulsion segment include a partnership with Korea Research Institute of Ships and Ocean Engineering (KRISO) to advance commercial SMR-powered ships and floating SMR power generation platforms.