The commercial shipping industry is chasing a novel carbon-free propulsion technology as it pursues a lofty climate goal: nuclear power.
Shipping accounts for more planet-warming greenhouse gas emissions than Japan. The sector is responsible for 3% of all emissions globally, but the international body overseeing it has pledged to cut climate pollution by as much as 30% by 2030 and eliminate it by 2050. Nuclear power — long a source of propulsion for the military — is a tantalizing solution for an industry largely reliant on highly polluting bunker fuel, though it will likely prove hard to insure.
While there are clean fuels in development like ammonia, the dearth of affordable options to power massive cargo ships has created an almost “insurmountable problem,” according to Mikal Boe, chief executive officer of Core Power Ltd. In a bid to address it, his company is leading an effort that includes HD Korea Shipbuilding & Offshore Engineering and utility Southern Co. to develop commercial vessels powered by carbon-free nuclear reactors.
There are significant technical and regulatory challenges and higher upfront costs, but Boe said the approach has the potential to make ships faster and cheaper to operate while also being able to carry more cargo. “This is the solution to one of the biggest conundrums,” he said. “If we could do this right now, there would be an enormous pent-up demand.”
The Core-led group is focused on getting a fission-powered vessel in the water by 2035. They’re planning to use a reactor from TerraPower LLC, a climate tech company backed by billionaire Bill Gates, which expects to begin testing the design in 2029. Southern completed last year the first new nuclear power plant in the US in decades and will bring its expertise to bear.
The effort comes as nuclear power experiences a revival on land as well. Artificial intelligence is increasing energy demand, and tech companies and governments are turning to both traditional nuclear and betting on more futuristic forms like fusion and the small modular reactors that Core is looking to use.
The first oceangoing reactor was deployed on a US submarine in 1955. A handful of civilian vessels were developed starting with the NS Savannah in 1959, but most eventually retired due to high costs and technical issues. Today, there are about 160 vessels worldwide that rely on fission. The technology is primarily used in military vessels, especially aircraft carriers and submarines, as well as Russian icebreakers in the Arctic.
However, the commercial shippingindustry’s emissions targets have prompted companies to reevaluate the idea, according to Jose Esteve, offshore gas and power market leader for Bureau Veritas SA, a French product-testing firm.
Some companies are exploring the use of carbon-free fuels like ammonia while others are testing the addition of sails. AP Moller-Maersk A/S, the Danish container giant, is already operating container ships that run on low-carbon methanol, and other companies are using hydrogen to power vessels. But the supply chains to produce these fuels are still developing, and Esteve is skeptical they’ll be ready when big ships start requiring them by the ton at every port.
“Those alternative fuels will not be there when we need them,” he said. “Not at a cost that makes them a viable alternative.”
He’s more confident that the nuclear industry will be able to deliver reactors to transform the global fleet. Esteve expects to see the first ships powered by atomic energy tested by the middle of the next decade, with wider usage by the late 2030s.
Still, transitioning to a nuclear-powered fleet will require some significant changes to the regulatory landscape. For starters, commercial insurance companies won’t provide coverage for ship that runs on fission because the potential cost of a nuclear accident is simply too high. Without insurance, few civilian ports would allow a nuclear-powered cargo ship to dock. That’s not an issue for naval vessels that can dock in military harbors, but it makes the technology a non-starter for commercial shipping.
There are also significant safety and security concerns, according to George Moore, a scientist-in-residence at the Middlebury Institute of International Studies in Monterey, California. While the fuel expected to be used for shipping doesn’t have the high concentration of uranium needed for a weapon, it’s still radioactive and commercial ships would be vulnerable to piracy or sabotage. That raises the specter of an intentional nuclear incident. Commercial ships are also typically less durable than naval vessels, increasing the risk of an accidental radiation leak due to a collision.
While regulatory agencies could develop policies to address some of those concerns, Moore said the industry seems more focused on developing the technology and the potential market.
“The industry hasn’t looked at all these issues,” which makes developing ships a risky idea, said Moore.
At a meeting this month, the International Maritime Organization will be discussing potential changes to the safety code for nuclear merchant ships. The group is also likely to vote in October on whether to impose financial penalties on some polluting vessels.
New nuclear technologies may reduce some of the risk, Moore said. Navy ships typically used pressurized water reactors, which circulate hot water under high pressure. If there were an accident, that pressure means radioactive material could be dispersed over a significant distance, enough to imperil much of a port and any ships in the area.
But TerraPower and other companies are developing a new generation of reactors to operate at normal pressure. That would help reduce the danger area, known as the emergency planning zone, in the case of an accident. The goal, said Boe, is an emergency planning zone that’s no bigger than the ship.
If these issues can be addressed, a nuclear-powered ship would offer several advantages over vessels that burn fuel, even of the carbon-free variety. Most ships today sail well below their maximum speed, often as much as 30% to 40% slower than their engines are rated, which lowers emissions and reduces operating expenses by burning less fuel, said Boe.
But nuclear ships would have no emissions, and they wouldn’t need to pay for fuel, allowing them to travel at top speed. This would mean faster deliveries and higher revenue for shipping companies. Plus, big ships need big fuel tanks, which can take up precious space. That wouldn’t be necessary on a ship with a reactor, and Boe estimates there would be about 10% more space for cargo.
Nuclear-powered ships could also reduce downtime by cutting out the need to refuel. The typical container ship spends a total of about a month of every year just refueling, according to Sangmin Park, a vice president with HD Korea Shipbuilding and Offshore Engineering, who’s leading the company’s effort to develop a nuclear ship. The reactors under consideration for cargo ships may have enough nuclear fuel to last for decades, which is essentially the entire expected lifecycle of the vessel.
Shipowners will also save money by not buying fuel, though the payoff will take some time because the initial costs will be higher. Nuclear systems are pricey, and Park estimates that a new ship would cost double or perhaps even triple the price of a standard cargo ship. But over an expected 25-year life of a vessel, the total cost would be less than half, he estimates.
“The nuclear-powered ship is good for general emissions, but it’s also good for the economy in the long term,” Park said.
Top photograph: The ZIM Integrated Shipping Services Ltd. Chicago container ship sails out of the Yangshan Deepwater Port in this aerial photograph taken in Shanghai, China, on Monday, March 23, 2020. Photo credit: Qilai Shen/Bloomberg
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