Could LNG ships be powered by nuclear energy?

Among its findings, the study has identified that recently updated legislation and available classification society rules allow for a fresh approach to the design of nuclear powered vessels.

Babcock says that its study has been undertaken at a time when the industry has shown renewed interest in nuclear powered commercial ships. The first nuclear propulsion in merchant ships was introduced in the 1960s, following successful exploitation in submarines and aircraft carriers, but while these were technically successful, they were commercially less so. Recently, Babcock believes that a number of factors have led to renewed interest. These factors include environmental concerns (notably over CO₂ emissions and other air pollutants), and the rising price of fossil fuel (beginning to make nuclear power far more competitive), along with the development of nuclear propulsion that has been on-going over the years (largely centred on icebreakers but also including other merchant ship types) with recent papers concluding that the adoption of nuclear propulsion for high speed container ships is technically feasible. According to Lloyd’s Register, some 600 or so nuclear reactors are operating worldwide today, of which about one third are serving at sea.

Babcock’s study was undertaken to determine the commercial feasibility of using nuclear power for main propulsion and auxiliary power generation on board an LNG carrier. The company believes that a number of benefits could be realised by the use of nuclear powered vessels for LNG transport. The nuclear plant would eliminate CO₂, NOx and SOx emissions. Additionally, the vessel’s large power generation requirements would be supplied by a relatively compact power source compared to normal power methods for this vessel type – a space saving that would maximise cargo capacity. Further benefits would include a significant reduction in noise generation, reducing the environmental impact of the vessel.

Babcock’s investigation covered key aspects ranging from engineering and design issues, recent technical developments, and statutory regulations, to operational aspects, through-life maintenance, training requirements, and vessel disposal.

Babcock’s Integrated Technology arm within the Marine division claims many years’ experience in complex vessel concept work and on LNG projects, and the Marine division has been sole UK in-service support contractor for the Royal Navy’s nuclear submarine flotilla for several years, undertaking refits and upgrades, supporting operational submarines, and providing engineering design and technical support services. Personnel involved in ship design, nuclear plant systems installation, maintenance, and decommissioning were involved in undertaking the feasibility study.

Babcock’s Integrated Technology commercial projects director David Dobson said that the study indicates that particular routes and cargoes lend themselves well to the nuclear propulsion option, and that technological advances in reactor design and manufacture have made the option more appealing. It has also confirmed significant benefits in terms of environmental impact and sustainability. Further, in reviewing the latest updated legislation, it is evident that newly issued design codes from Lloyd’s Register allow the design of nuclear powered vessels to be re-visited. On the other hand, initial capital costs are high (although they will reduce significantly when more applications for commercially produced marine reactors are found) and commercially available building and maintenance facilities would need to be established if significant numbers of these ships were to be planned.

“Nuclear power for commercial vessels is becoming significantly more attractive on a number of counts, not least from an environmental perspective, but there are a great many issues to weigh and consider in determining the feasibility of nuclear propulsion for any commercial vessel,” Dobson says. “Our knowledge and experience puts us in a particularly strong position to identify and advise operators on these issues. We have worked with several of the major operators in the marine and oil and gas sectors on a number of ground-breaking developments in FPSOs and LNG vessels over the years, and are delighted to be again investigating new ground.”