The cargo shipping industry is slowly finding its way towards low emission fuels, but in the meantime wind power is ready and eager to go. Various forms of high tech sails are reappearing on shipping lanes, and to gild the sustainability lily, some of them are made with recycled plastic bottles.
Wind Power Is Ready To Roll
Massive cargo ships can’t run solely on wind power, of course. However, when the new generation of rigid, aerodynamic sails is combined with pinpoint planning for optimal shipping routes, the fuel savings is significant.
Last August, a Sumitomo tanker outfitted with Rotor Sails demonstrated the fuel saving on cross-Atlantic trip between New York City and Amsterdam. Norsepower reported that wind power contributed 16% of the fuel savings, with route optimization kicking in another 12%.
The company also reported an average savings of 19% for six different long distance routes, with wind power contributing 9% and route optimization adding another 10%.
Crazy Looking Sails Are Not So Crazy After All
Rigid sails on cargo ships typically share some similarities with the sleek aerodynamics of the sails sported by modern racing yachts, but Norsepower’s contribution to the field comes from a different place. Instead of harvesting wind power from relatively flat surfaces, Norsepower deploys Flettner rotors in long, tall tubes that resemble smokestacks.
“The rotor sail utilizes the Magnus effect to create thrust and propel the ship forward,” Norsepower explains. “When wind meets the surface of the visible, spinning rotor part of the sail, the air flow accelerates on one side and decelerates on the opposite side of the rotor sail. The change in the speed of air flow results in a pressure difference.”
If you can throw a curveball, you can see the Magnus effect for yourself.
Wind Power That Tilts, Now With Recycled Plastic
Norsepower designed the Rotor Sails to tilt into a flat position when needed, which answers the question of how they can fit under low hanging bridges.
In the latest sustainability twist, Norsepower has introduced recycled plastic bottles into its wind power mix.
That’s not entirely unprecedented in the sailing world. In 2009, for example, a sailboat made with 12,500 recycled plastic bottles set sail on a research voyage.
Bringing things up to date, just last year the Swedish wind power firm OceanBird posted a lifecycle analysis of their new “Wing 560” rigid sail in which they noted that the composite used in the sail is made partly with recycled plastic.
In a case study published last November, Norsepower provided some details to Nefco, the Nordic Green Bank, about its own combination of wind power and recycled plastic. “We use a raw material based on recycled PET plastic bottles in our Rotor Sails,” Norsepower CEO Tuomas Riski told Nefco. “A typical sail can contain 300,000 recycled PET bottles.”
Onwards And Upwards For Sailing Cargo Ships
New ships that are purpose-built to optimize hard sails are just one market for Norsepower. The other is the retrofit market, and that’s where things could scale up rapidly.
Earlier this week, Norsepower announced that the shipping firm Oldendorff Carriers will install three Rotor Sails on its Dietrich Oldendorff bulk carrier vessel, meaning a ship designed to carry liquids, grains and other non-packaged substances. The project is expected to be completed around mid-summer.
“The huge, spinning rotors are partly manufactured from approximately 342,000 plastic bottles,” the company explained in a rather significant uptick from the figure cited last fall.
Apparently Norsepower is already eyeing the potential for hundreds more retrofits.
“Oldendorff is a dream customer for Norsepower in more than one way: a family-owned, legendary, company with over 100 years operating in the industry and around 700 vessels on the water today,” Tuomas Riski said in a press statement.
“I wholeheartedly welcome Oldendorff’s commitment to Norsepower’s mission of decarbonizing shipping and look forward to the next possibilities for cooperation!” he emphasized.
Wind Power For Thousands Of Ships
Norsepower estimates that almost 30,000 vessels of various types, including passenger ships, could be retrofitted for wind power with Rotor Sails. In another indication that Norsepower is gearing up to scale up, on October 31 the company announced that the shipping firm IINO Kaiun Kaisha, Ltd. and the Mizuho Leasing Company are collaborating on a leasing program for the Rotor Sail. The agreement is aimed at shaving down the up-front cost of installation.
“This initial investment can be a significant barrier to technology take-up for small to medium-sized shipowners and operators, despite the achievable fuel consumption, GHG and other emissions reductions,” Norsepower explained. “This failure means that thousands of vessels on the water today are missing out on the potential benefits of the Norsepower Rotor Sail.”
Norsepower is among those who foresee that alternative shipping fuels will barely make a dent on greenhouse gas emissions in the near future, leaving wind power to hold the bag.
“The [lease] concept is being developed amid growing recognition that GHG and other emissions reductions with low carbon or green fuels alone prior to 2030 will be minimal. This is due to the limited availability of alternative fuels, placing an onus on energy efficiency solutions like Norsepower Rotor Sails to maximise energy efficiency savings,” Norsepower observed.
“Vessel and cargo owners have already used the product for nearly 10 years, accumulating around 300,000 operating hours of verified performance data that show average fuel consumption savings of between 5-25%, or more in good conditions,” Norsepower also notes. “These savings have been measured and analysed independently in various projects by Lloyd’s Register as well as ABB, NAPA, RISE, Chalmers University of Technology and VTT.”
What About Alternative Fuels?
As mechanical devices, rigid sails are not subject to the same supply chain constraints that can obstruct alternative fuel use at scale. Still, with wind power as a bridge, the shipping industry will eventually detach itself from fossil energy.
Here in the US, the Navy got the ball rolling with the launch of the Great Green Fleet, showcasing biofuels alongside nuclear energy. If such an exercise were to take place today, hard sails would most likely make an appearance in addition to new alternative fuels and technologies.
Considering the improvements in battery technology since the early 2000’s, it’s no surprise to see the leading maritime firm Yara launch an all-electric bulk carrier in Norway. The ship has been making the rounds since 2022, and Yara is currently in the process of activating the ship’s autonomous controls.
Green hydrogen is another new development that is beginning to show up in zero emission hydrogen fuel cells. It is also the chief ingredient in green ammonia, which the shipping industry is eyeing as a lower-emission fuel.
Aside from financial and supply chain considerations, the risk of environmental impacts complicates the alternative fuels picture, so for now it’s up to wind power to do the heavy lifting for maritime decarbonization.
Or, people could just buy less stuff that has to be shipped around the globe. That could work, too.
Image: Cargo ship outfitted for wind power with Rotor Sails (courtesy of Norsepower).
Follow me @tinamcasey on Bluesky, Threads, Post, and LinkedIn.
Have a tip for CleanTechnica? Want to advertise? Want to suggest a guest for our CleanTech Talk podcast? Contact us here.
Latest CleanTechnica TV Video
I don’t like paywalls. You don’t like paywalls. Who likes paywalls? Here at CleanTechnica, we implemented a limited paywall for a while, but it always felt wrong — and it was always tough to decide what we should put behind there. In theory, your most exclusive and best content goes behind a paywall. But then fewer people read it!! So, we’ve decided to completely nix paywalls here at CleanTechnica. But…
CleanTechnica uses affiliate links. See our policy here.