Tomorrow’s phantom ships

Posted: September 23, 2024

The Swedish ship captain couldn’t make sense of what he was seeing. Off his starboard bow, a Danish ship, the Selandia, was signaling him to change course. Collision was imminent if he didn’t give way. But her warnings didn’t make sense.

He was crossing well ahead of her—and she wasn’t even moving. She couldn’t be moving. She had no sails. No smoke was pouring out of her smokestack from coal-fired furnaces—she didn’t even have a smokestack. She appeared to just be sitting in the middle of the Öresund, the strait of water between Denmark and Sweden.

As the captain continued on his course, a mind-boggling reality began to set in. The Selandia was, in fact, coming toward his starboard side—and fast. Somehow this mysterious ship was moving without sails, without coal, without a smoke-stack.

The Swedish captain’s ship ran directly across the Selandia’s bow, clearing it just in time to avoid collision. The Selandia was one of the first diesel-powered ships. At the time of this near-miss in 1912, it was out on its first test run, just months before the steamship Titanic left on her ill-fated voyage. Ivar Knudsen, lead engineer of the Selandia,  described how preternatural the ship’s movement looked to the throngs who came to watch her, gliding up the Thames or slinking into San Francisco Bay:

“The almost silent, swan-like passage of these ships through the water, without a smoke-stack, gave cause for an American's description of one of them as a ‘phantom ship.’”

Others, disconcerted by the new so-called “smokeless ships” described the vessel as “the Devil Ship.”

Diesel shipping wasn’t magic. It was more efficient than the coal-powered steam-engine vessels, which had put an end to the great age of sail in the second half of the 19th century. But it did more than just increase efficiency. It changed the economics and logistics of commercial shipping in profound ways. Diesel ships could travel farther without stopping for fuel and required fewer crew. Fewer crew meant less expense, and less stopping meant faster shipping times—all of which meant cheaper, more widely available goods.

In the early 20th century, a transatlantic steam liner would have something like 370 crew just devoted to ship operations, along with another 500 stewards. The engine department alone required 300 people—most of them manually stoking the coal-burning furnaces. The other 70 worked the deck, steering, keeping lookout, and performing maintenance.

The new diesel ships no longer required crew to manually feed furnaces, so engine crew requirements plummeted. As more ship tasks became automated over the next 100 years, ships also required fewer crew for navigation, monitoring and maintenance. By the 1950s, a steam-powered cargo ship only required a crew of 40-50. By the 1990s a diesel cargo ship required just 21 crew total. That’s about the number on a Maersk container ship today, though some make do with as few as ten or 13. 

Over a hundred years since the Selandia astounded spectators by seeming to move without wind or fuel, you can now observe a different kind of phantom ship.

The world’s first zero-emissions autonomous ship

If you look out the window of the library in Stathelle, Norway, out onto the waters of the Frierfjord, you might see a blue, 80-meter container ship quietly gliding under the suspension bridge that spans the fjord. It’s transporting ferilizer from the Yara production facility 11 nautical miles up the fjord in Porsgrunn. This ship, the Yara Birkeland, doesn’t have any sails or smoke: it’s fully electric. The words “zero emission” stretch proudly across her sky-blue hull.

The sight of an all-electric ship might elicit an exclamation of “cool!” though nothing like the bewildered wonder that the diesel-powered Selandia inspired 100 years ago. But, if you continue watching the Yara Birkeland, you might start to get the sense that something else is a bit uncanny about her. Especially if you see her pull into the unloading quay in Brevik and dock without the help of any crew.

The Yara Birkeland is the world’s first zero-emissions autonomous ship. It can leave its quay at the fertilizer facility, navigate 11 nautical miles through the fjord to Brevik, dock at the unloading quay, and then depart on its return voyage without intervention from a single human. It’s already done this 175 times since launching in 2022.

Radar, infrared cameras and other sensors feed an AI system that navigates the ship around obstacles, other ships and the weather. Machine learning algorithms help it learn how to navigate better as it gets more experience.  

Right now, three crew members do ride on board, largely to fulfill regulatory requirements to monitor the ship and stay prepared to take manual control if it becomes necessary. Soon, the crew will go down to just two once the electrician moves to the new remote operations center in Horten. There, 40 miles away from the ship’s route, crew can monitor and, if necessary, control the ship remotely. While the Yara Birkeland can dock autonomously, it does still require human help mooring at the dock. But, it’s testing robotic mooring arms, which will automatically loop mooring ropes around bollards on the dock.

As autonomous technology improves, more ships will start to operate like the Yara Birkeland. Project manager, Jostein Braaten says:

“It is no longer a question of if autonomy is coming, it is a matter of when.”

A digital infrastructure for shipping

Today, many companies are at work creating a digital infrastructure that will make expanding autonomous shipping easier. The U.K. Hydrographic Office is formatting its maps so that autonomous piloting programs can read them, and the International Hygrographic Organization is creating what it calls a “digital twin of the navigable waters.” 

This digital twin will be like Google Maps for shipping—a digital model of maritime routes that maps seabed topography, ocean currents, weather forecasts, warnings, and even simulations of water conditions. It will collate data from local weather services, harbor authorities and hydrographic offices. You can easily imagine a not-too-distant future in which autonomous ships pull real-time data from these maps to adjust routes that optimize and trade-off fuel efficiency and speed, all while steering clear of other vessels.

Digital twins and simulations are also helping design ships with new propulsion technologies. In 2020, the America’s Cup yacht race banned the use of wind tunnels and water tanks to design vessels. Engineers turned to digital simulations of virtual oceans. Out of such engineering simulations were born technologies like WindWings, vertical, rigid wings that stretch over 37 meters above a ship’s deck. The vertical wings propel ships across the water using the same aerodynamic principles airplane wings use to lift planes into the sky. 

These new technologies often rely on autonomous piloting. Cargill uses WindWings on one of its bulkers along with sensors that monitor wind conditions and automatically reconfigure the wing sails to optimize their performance—no crew needed. The ship-owner, Lomar, is creating a fleet of autonomous micro-sized cargo ships primarily powered by large kites. They use AI to calculate optimal routes at sea in response to real-time weather conditions. 

What is the future of autonomous shipping?

Even if it’s several years before fully-autonomous, crewless ships become the norm, ships are bound to become more autonomous by degrees. Kongsberg Maritime VP, Ville Vihervaara, told CNBC in April:

“It really much depends on regulation, how the different countries and maritime regulators, how soon they will allow unmanned or uncrewed vessels at sea.”

The International Maritime Organization is working on a regulatory framework for autonomous shipping, and the UK has entered an agreement with Norway, Belgium, Denmark and the Netherlands to coordinate their use of autonomous ships within the North Sea Basin.

As with the advent of diesel ships a hundred years ago, autonomous shipping will likely have widespread economic effects. It will keep more seafarers out of harm’s way and reduce shipping accidents due to human error. It also promises to reduce CO2 emissions along with generally reducing the costs of shipping goods—just as the reduced crew and fuel expenses of diesel ships did over a century ago.