Global shipping is a big business. Roughly 90% of the world’s consumer goods get loaded onto a cargo ship at some point, and the industry is vital to the global economy. However, being a big business means having a big carbon footprint. Burning the extremely dirty ‘bunker fuel’ means global shipping is responsible for up to three percent of all global carbon emissions, and a similar portion of methane and other greenhouse gas emissions.

Obviously, such a vital industry can’t just be shut down. But, as climate change becomes a more and more imminent threat, something has to be done to mitigate this emissions catastrophe. Ignoring shipping in a plan to mitigate climate change would be like ignoring the emissions generated by economies like Germany and Japan.

Meanwhile, existing efforts to decarbonize are basically non-existent. Despite promises to cut emissions in half by 2050, the International Maritime Organization still projects emissions could increase by as much as 250%, and its efforts to decarbonize are already off the rails. The shipping company Maersk has pledged to cut emissions completely by 2050, but has no plan to do so and even if they did, 2050 is likely too late.

So, what to do? Well, there’s already a proven way to power ships with exactly zero emissions, doesn’t negatively affect transit times and is in use today. That’s right, nuclear power. The best way to mitigate the carbon emissions caused by the shipping industry is to replace as many dirty bunker fuel-burning engines as possible with clean, modern nuclear reactors.

Is it Even Possible?

As pointed out above, the technology required for nuclear-powered ships is already used in navies across the world and has been in use since 1955. Such ships have huge advantages for military use, and many of these would transfer to seamlessly to civilian life, like longer range, greater flexibility, and of course, reduced emissions.

Of course, military technology might not be available for civilian use, but that might not matter—four commercial nuclear-powered ships have been commissioned in the past. The most famous of these is the NS Savannah, built under the Eisenhower administration to showcase America’s postwar power, and the other three were built by Germany, Japan, and Russia.

The Savannah never really worked out, but that had nothing to do with its power source. IT was always intended as a showboat power, and as such its modern design was hardly conducive to carrying the amount of Cargo it would have needed to break even. The fact that it was one of the last break bulk ships built before the container revolution didn’t help either.

Meanwhile, Germany’s Otto Hahn and Russia’s Sevmorput combined for nearly three decades of consistent, profitable operations, with the former being even more efficient than ships of comparable size due to lower fuel cost. Japan’s Mutsu did hit a stumbling block, though. Public backlash following a minor radiation accident put a major dent in the project, though it’s worth noting that despite this, there were no casualties. The ship was still able to complete tests and it was merely decommissioned early.

Long Term Benefits

So clearly, the historical record shows that nuclear-powered cargo ships are possible and even economical given sufficient care. But what about the modern day? If anything, there’s more to like. Besides eliminating carbon, nuclear power would almost certainly be cheaper over a ship’s lifespan, with most of the costs being the (admittedly more legitimate than usual) regulatory barriers.

But even if costs are higher, it would seem reasonable for governments to subsidize a transition. It makes sense because cargo ships are so huge, so each one that runs on nuclear power instead of dirty bunker fuel has a massive impact. With reactors costing a maximum of 200 million apiece (and likely less, because cargo ships require less propulsion that aircraft carriers), a potential transition would be relatively cheap. With each conversion taking out tons and tons of carbon emissions, it’s incredibly cost-effective. Even converting all 6000 or so full-sized container ships at that price would cost 1.2 trillion—a lot of money, but substantially cheaper, and more bang for your buck, than other climate policies like a Green New Deal.

What About the Alternatives?

Despite the obvious benefits of a nuclear-powered cargo fleet, there could be other options. In recent years, the green energy industry has exploded, leaving us with all kinds of renewable options to power our society, from ultra-efficient solar panels to more and more wind turbines. However, despite their success being deployed elsewhere, none of these methods would work as well for cargo ships as nuclear.

Solar panels and wind turbines simply can’t generate enough energy to power a massive ship. Currently, available products can only power the lighting, meaning something needs to be done to actually move the ship forward. Even the most ambitious solar-wind combination projects only boast energy savings of 40%. Leaving 60% of emissions from cargo ships intact still leaves us in the same neighborhood as Mexico, emissions wise.

Recent attempts to go back to the old days of sailing the high seas run into the same problem. Estimates go as high as getting 50% of propulsion generated by sails, but that’s still not enough when we already have a way to get 100% of propulsion generated by a system that already exists. This isn’t to say that technologies like sails, solar panels, and wind turbines shouldn’t be used at all—there’s certainly a place for them, but to get the full effect, they should be used to enhance, not replace, nuclear technology.

Just as importantly, there’s no clear reason to prefer other forms of energy over nuclear. Even if alternatives might eventually work, we have the technology to implement nuclear-powered ships right now. Given the urgency of the climate emergency, that should be enough for anyone to prefer it. The case is only strengthened by nuclear being the empirically safest form of power, and being free of any major incidents at sea, despite nuclear-powered icebreakers roaming the arctic for decades.

In Conclusion

Given the weight of the evidence, it’s clear that switching cargo ships over to nuclear power should be a major goal of any climate plan. With the global shipping industry making up nearly 3% of global emissions, it only makes sense to use readily available and carbon-free technology to rectify that. Especially one that has worked in every situation it’s been deployed in.

While the initial costs of nuclearization might require government subsidies, the massive return on investment should make the governments happy to pay. Even if they aren’t, the long term return on investment means shipping companies should be equally happy to indulge, making the government’s task as simple as loosening regulations to make sure it can happen.

With so much at stake, it only makes sense to make sure as many container ships become nuclear-powered as quickly as possible. An opportunity to disrupt climate change as much as this rarely shows up, so it’s up to all of us to make sure we take it.