Amazon and DHL are talking about using drones to deliver packages by air; Google and Tesla about driverless cars.
Some futurists are even hinting at crew-less ships.
Rolls Royce got a lot of publicity earlier this year when Oskar Levander, vice president of innovation, engineering and technology, ruminated about drone ships in an article posted on the engine maker’s website that also discussed alternative fuels and propulsion systems.
“A growing number of vessels are already equipped with cameras that can see at night and through fog and snow, and have systems to transmit large volumes of data,” he said. “Given that the technology is in place, is now the time to move some operations ashore? Is it better to have a crew of 20 sailing in a gale in the North Sea, or say five in a control room on shore?”
One benefit, he noted is that “the same person can monitor and steer many ships. As conditions ashore are often preferred, it will also help retain qualified and competent crew, and is safer.”
Eliminate or reduce the size of a crew and Levander contended “vessels could be radically simplified. Attitudes and ways of working will need to change, but safe operation is possible, particularly for vessels running between two or three fixed points.”
In September, the classification society DNV GL, revealed a “concept ship” for short-sea shipping. Much like those “concept cars” that you might see at the Detroit Auto Show, it incorporates a boatload of leading-edge ideas.
DNV also cited improved safety as a major benefit for using a crew-less ship.
The firm called this its ReVolt project—as the name suggests, the ship would be propelled with electric motors powered by batteries. The ship could be zero-emission, it added, if the batteries are recharged with electricity from a renewable source such as hydro.
“Building and operating this vessel would be possible with today’s technology,” said Hans Anton Tvete, a senior researcher at DNV.
In a Marine Impact article, DNV said off-the-shelf technologies, such as electronic chart displays and information systems, global positioning satellites, radar, cameras, and light detection and ranging (the use of radars to measure distance), if combined, “have the potential to create complete situational awareness around the vessel.”
But it also said the idea of having a ship operate autonomously “takes the applied technologies to the extreme” and many intermediate steps “such as condition and sensor-based monitoring, enhanced navigational assistance and remote operation, will have to be taken before unmanned ships can become a reality.”
“ReVolt is intended to serve as inspiration for equipment makers, shipyards and shipowners to develop new solutions on the path to a safe and sustainable future,” Tvete said.
The ReVolt project looked at the economics of a small ship carrying 100 TEUs and used on routes with individual legs of less than 100 miles. DNV said it came up with the operational profile by looking at automatic identification system data for vessels operating currently in the Norwegian Economic Zone.
Unlike most concept cars, ReVolt would be slow, operating at just 6 knots. DNV said “as a consequence of this low speed, the logistics chain will have to be redesigned entirely,” but suggests that a service with frequent departures, and four hour average port stays “could create the right conditions for transferring appropriate cargo types to this mode of transport.”
Slow speed has its advantages, however—since cavitation will be negligible, DNV said it can use propellers with just two blades, allowing for more efficient propulsion.
Suppose the ship was powered with hydroelectricity, DNV said in that case “energy loss from the water reservoir to the propeller is estimated to be as low as 40 percent. By contrast, comparable diesel powered ships may suffer well-to-propeller losses of up to 85 percent.”
(One of DNV’s competitors, the American Bureau of Shipping, recently ran a series of articles about propellers in its Surveyor magazine. It noted as slow steaming has been embraced by the shipping industry, many shipowners are “boosting fuel economy by changing propellers and, in particular, taking advantage of propulsion solutions provided by leading propeller maker Mecklenburger Metallguss.” Combined with advanced rudders and other energy-saving devices, retrofit propellers can boost fuel efficiency by 10 percent, the propeller maker said.)
The ReVolt project envisions a ship with two propellers located in stern pods and assisted with a retractable bow thruster.
DNV said podded propulsion units have fewer rotating parts than conventional rotating propulsion, and hence would require less maintenance. They would be located outside the ship’s hull. The pods and a retractable bow thruster would allow it to maneuver without a tug.
Batteries would also reduce maintenance costs. However, it stated the battery pack on such a ship would be extremely capital intensive and need replacement about halfway through the 30-year estimated life of the ships.
As the ReVolt ship was designed to move slowly and spend minimal time in port, DNV said it designed the vessel to be easily worked.
“By raising the hull sides and cell guides to full container stack height, cargo handling can be accelerated while eliminating the need for stevedores and manual lashing,” DNV explained. “To ensure fast transfer of cargo from the ship to other modes of transportation, the shoreside facilities in ports need to be highly efficient. This can be achieved by building dedicated terminals with easy access for trucks.”
DNV contends such a ship would be profitable from day one, and lower energy, maintenance, and crewing costs would save $34 million over the life of a ship.
This column was published in the November 2014 issue of American Shipper.
