Zero-emission shipping: time to consider the nuclear option?

While nuclear power “presents a very interesting path” to decarbonise shipping, it first must overcome significant barriers — most notably the public’s perception of its safety risks, current regulations, capex and crew training, according to a leading class expert.

Speaking at Riviera Maritime Media’s Maritime Decarbonisation Conference, Asia, in Singapore in April, Mike Watt, director of innovation at Bureau Veritas’ Centre of Alternative and Renewable Energy (iCARE), detailed those barriers, while providing an intriguing glimpse at the environmental benefits of nuclear power.

“You only have to talk to the common man in the street and understand that it could be difficult to convince local populations of the benefits and safety of this energy,” said Mr Watt. Beyond educating the public about nuclear energy’s strong safety record, Mr Watts said shipping would have to navigate strict international and national regulations governing the use of nuclear power or transport of nuclear material. “These regulations could make it challenging to operate nuclear-powered merchant vessels across the world and across different jurisdictions,” pointed out Mr Watt.

He cited Article 23 in the United Nations Convention on the Law of the Sea, which states: “Foreign nuclear-powered ships and ships carrying nuclear or other inherently dangerous or noxious substances shall, when exercising the right of innocent passage through the territorial sea, carry documents and observe special precautionary measures established for such ships by international agreements”.

There are also existing International Atomic Energy Agency and SOLAS Chapter 8 regulations governing the safety and construction of nuclear-powered merchant ships. On top of regulatory challenges, there are crew training and competency issues and the expense of building nuclear-powered vessels, which cost significantly more than fossil fuel-powered ships to build.

“Nuclear presents a very interesting path in decarbonisation”

But putting these challenges aside for the moment, Mr Watt was still upbeat about nuclear power, pointing to the promising advances in the technology, such as small modular molten salt reactors (MSRs) for marine use. These more compact units differ from pressurised water reactors and do not need to be refuelled, operate at ambient pressure and use molten fuel salts (low-enriched uranium/thorium) instead of fuel rods. He mentioned that Thorcon, Core and Seaborg were working on applying MSR technology for marine applications.

“Nuclear-powered merchant vessels have the potential to revolutionise the shipping industry by providing significant advantages in terms of speed, efficiency, and environmental sustainability,” said Mr Watt, highlighting the potential benefits to long-haul cargo transport. “These vessels would be able to carry large amounts of cargo over long distances quickly, efficiently without the need for frequent bunkering stops. Nuclear presents a very interesting path in decarbonisation,” he added.

There Is extensive experience in nuclear-powered naval ships and submarines and some limited applications of merchant nuclear-powered ships, with mixed success in the US, Japan, Germany and Russia, the latter of which has been operating the merchant cargo ship Sevmorput since 1988.

Among the first potential marine applications, nuclear could be used to provide floating electric power, supporting ports and battery-powered vessels to reduce the use of fossil fuels, or in the floating production of e-fuels, such as hydrogen, ammonia, methane and methanol.