Why You Don't See Many Nuclear-Powered Cargo Ships

Shipping ain’t easy. You’ve got record-breaking storms knocking containers into the ocean, backed up ports, and countries taking your crews into escrow — and pollution. So much pollution. To the point where some interests are looking into putting nuclear engines into cargo ships.

Now, plenty of ships in the ocean use nuclear power, just not cargo ships. Aircraft carriers, ice breakers, and submarines, sure, but the only cargo ship running running on protons is a tiny Russian cargo junker called the NS Sevmorput. The U.S. tested a nuclear-powered Cargo ship, but it only ran for five years in the ’60s

Why is that? Considering how dirty the shipping industry is, you’d think they’d jump at the chance at some clean energy. Wired has a great look at efforts to revive the nuclear-powered cargo ship:

But figuring out what to do with a ship’s reactor is far from the only hurdle. People need to be convinced of the safety of nuclear energy and technology, says Alves de Andrade. Despite excellent safety records at many nuclear sites around the world, public perceptions remain understandably dominated by the Chernobyl and Fukushima disasters, as well as by concerns around what to do with radioactive waste.

And while there are lots of nuclear reactors operating at sea right now, they tend to be on vessels with some of the highest security in the world. Commercial ships are occasionally subject to piracy and accidents, including large fires and explosions—the thought of adding nuclear fuel to such scenarios is unlikely to be met with enthusiasm.

The task of switching to a world in which nuclear-powered vessels are commonly welcomed at commercial ports is “not trivial,” says Stephen Turnock, professor of maritime fluid dynamics at the University of Southampton. “You have to have protocols in place to say what would happen in the event of an emergency associated with a nuclear-powered vessel,” he explains.

Simon Bullock, a shipping researcher at the University of Manchester, says that there is not enough of a regulatory framework to define how nuclear ships would operate globally in the commercial sector, including detail on who would bear responsibility for any mishaps. Would it be the ship owner, the ship operator, the manufacturer of the nuclear reactor, or the country where the ship is registered, known as the flag state? There are six “decade-long problems” of this kind regarding nuclear vessels that the International Maritime Organization (IMO) and other agencies would have to sort out if nuclear-powered commercial ships were ever to become widespread, he says.

Liz Shaw, an IMO spokesperson, says that “there is a long history of IMO cooperating and coordinating with other entities where necessary.” There are guidelines for how member states may submit proposals to update existing regulations, she adds.

The crews on nuclear ships would also require special training and expertise, which raises the cost of running such vessels. Is it worth dealing with all these challenges, given the need to decarbonize right now? Probably not, says Bullock. “The critical thing here is the next 10 years,” he says, referring to the urgency of tackling emissions and climate change right now. “Nuclear can do nothing about that.”

A Norwegian company and a South Korean company are fooling around with designs, including a molten salt reactor; a technology that’s been around since the late ’60s. Cargo ship pollution are responsible for 60,000 premature deaths every year, Vox reports.