Cargo Shipping with Nuclear Power?

Nuclear propulsion includes a wide variety of propulsion methods that use some form of nuclear reaction as their primary power source. The idea of using nuclear material for propulsion dates back to the beginning of the 20th century. It was hypothesized that radioactive material might be a suitable fuel for engines to propel cars, trains, planes and ships. Save for a few exemptions, this never materialized for various (technical) reasons, but now there are new initiatives that want to use recent technical advances for nuclear-powered cargo shipping.

The idea of using radium for propulsion first emerged in the early 20th century, even inspiring legendary science-fiction writer H. G. Wells in his 1914 novel “The World Set Free”. Especially shortly before and after the first atomic bombs were dropped, which led to the end of World War II, humanity naively believed that with the start of the “nuclear age”, every problem would be easily solved. The power of nuclear fission was to be used not only to generate energy, but also in everyday life. Now, the euphoria has somewhat evaporated, as the technology is fairly safe but not entirely risk-free, and the question of how to store the spent fuel rods is still unresolved.

An optimistic start to a new era

Although a 1937 concept for a nuclear-powered car indicated that the driver might need a 50-ton lead barrier to shield them from radiation, engineers worked tirelessly throughout the 1940s and 1950s to come up with a viable concept. The development of the first nuclear-powered submarines and ships, as well as experiments to develop a nuclear-powered aircraft (!) kept the idea alive despite the shielding problem. Even the Soviets reported the development of a nuclear-powered car, and it was claimed that their laboratories had overcome the shielding problem with a new alloy that absorbed the rays.

“Atomic road cruisers”

In 1958, at the height of the 1950s’ classic American automobile culture with its huge and legendary “cruisers”, at least four theoretical nuclear-powered concept cars were proposed. Their names were self-explanatory or at least sounded very extravagant, like the Ford “Nucleon” or the Studebaker-Packard “Astral”. Except for these concept models, none were ever built. A Chrysler engineer even rejected the idea in 1957, estimating that a 36-ton atomic engine would be required to move a car weighing 1,400 kg. Back then, the technical possibilities to use nuclear energy were simply too cumbersome to be practical.

Splitting atoms instead of “Choo Choo”

In the mid-1950s, Dr. Lyle B. Borst, a physics professor at the University of Utah, had a great idea: If cars were too small as a platform, one could use trains – with their much larger size – to cross the vast distances of the American continent with the help of the new energy source. The problem of shielding against harmful radiation would also have been easier to solve in a locomotive than in a small car. In addition, regular locomotives at the time had to make frequent stops to load up on coal or diesel. How much better would a locomotive be that could travel around the world without even stopping to refuel?

Dr. Borst, who had formerly been a reactor designer, developed the X-12 together with students of his physics course and in cooperation with several mechanical engineering companies. The X-12 was set to be a nuclear-powered locomotive, and a 54-page feasibility study was published for the ambitious idea.

A powerful, 360-ton monster

The X-12 would have weighed 360 tons and been almost 50 meters long – so long that the engine would have had to be divided into two sections, with a flexible vestibule connecting them. The nuclear power source would have been a solution of fissionable U-235, contained in a small tank. This container, only one meter long and 30 cm wide, would have been enclosed within a 200-ton shield. Steam produced by the reactor would power turbines which would drive four generators. These would create the 7,000 horsepower of electricity required to power the motors driving the wheels. It would have been powerful enough to accelerate a 5,000-ton train to almost 100 kilometers per hour in just 3 minutes and 32 seconds.

Only ships were realized

Well, while technically very impressive, the broader consequences of the spent nuclear “fuel” were treated too lightly. In the end, most of these trains, cars, and planes only reached the status of technical drawings or prototypes. Only special-purpose ships like icebreakers or aircraft carriers were successfully developed and are still in use today.

Recently, there has been a renaissance in the use of nuclear propulsion in shipping. This is driven by several factors, but above all, technological progress in the miniaturization of nuclear technology has played a key role.

A new renaissance dawning?

In August 2024, Maersk, announced their partnership with “Lloyd’s Register” and “CORE POWER” to study the feasibility of nuclear-powered container ships as part of their efforts to reduce emissions in maritime transport. A joint study focuses on advanced fourth-generation nuclear reactor technology, known for its enhanced safety features, and aims to address challenges such as regulatory approval, safety, and operational efficiency.
The biggest advantage of integrating nuclear power into logistics operations: potentially emission-free shipping, essential for meeting carriers’ self-imposed net-zero targets.

More carriers are interested

Despite its potential, nuclear-powered shipping faces challenges such as safety concerns, waste management, and regulatory hurdles. Ole Graa Jakobsen, Head of Fleet Technology at Maersk, recognizes these issues but remains optimistic about technological advancements in reactor design over the next ten to 15 years.

But other carriers are also exploring nuclear propulsion in their endeavors to significantly cut emissions. Ocean Network Express (ONE) and Hapag-Lloyd have shown interest. ONE sees nuclear energy as a complement to green hydrogen production, another leading contender for sustainable maritime fuel. Meanwhile, Hapag-Lloyd CEO Rolf Habben Jansen sees potential for nuclear propulsion to play a role post-2030, though he emphasizes that the technology is still in its early stages.

2,800 or 24,000 TEU?

One of the aforementioned companies, CORE POWER, has taken a leading role and unveiled a concept for a 2,800 TEU nuclear-powered container ship using molten salt reactors. These vessels promise faster transit times and zero emissions: On transatlantic routes, for example, travel times could drop from ten days to 6.5 days, significantly boosting operational efficiency. The only drawback: A capacity of 2,800 TEU is considered relatively small nowadays.

China’s shipbuilding industry is also making strides in this area, but takes a different approach. The state-owned “Jiangnan Shipyard” has revealed a design for a 24,000 TEU nuclear-powered container ship that also utilizes molten salt reactor technology.

Someday?

As shipping companies face mounting pressure to meet International Maritime Organization (IMO) emissions reduction targets, nuclear propulsion offers a potential pathway to decarbonization. While significant challenges remain, ongoing research and collaboration could make nuclear-powered shipping a reality within the next decade. Only time will tell how this new initiative develops and whether there will be a “new atomic age” in the transport industry…