Wing Sail Mobility
Michelin and inflatable sails on cargo ships
Michelin wants to adapt the technology to cargo ships. The goal is to harness wind energy to reduce the use of diesel fuel and thus curb greenhouse gas emissions.
The measure could increase a boat’s fuel efficiency by 20 percent.
The French tire manufacturer unveiled its Wing Sail Mobility project, or WISAMO, earlier this month. The setup works with the push of a button.
First, the telescopic mast rises from its base, reaching up to 17 meters in height. The wing, which starts out as a stack of fabric, slowly unfolds as a small air compressor inflates the double-sided material. As the wind flows over the 93-square-meter wing, variations in air pressure create lift, helping to propel the boat forward. When the boat approaches a bridge or encounters bad weather, the system automatically retracts.
Michelin estimates that the wing can improve a ship’s fuel efficiency by up to 20 percent, based on measurements from technical tests and simulations, said Benoit Baisle-Dailliez, who leads Michelin’s WISAMO initiative. For a large container ship, that could mean avoiding burning tens of thousands of liters of fuel on any given day. The company plans to test the technology on a commercial freighter in 2022.
WISAMO is a significant step towards Michelin’s ambition to fully decarbonize its supply chain
The project joins a growing fleet of “wind-assisted propulsion” initiatives around the world.
On the MV Afros bulk carrier, four Flettner rotors (or rotor sails) spin at a dizzying rate, creating thrust that pushes the ship forward. The Lysbris Seaways cargo ship is equipped with two suction wings. Non-rotating structures have internal vents and fans that draw in the thin layer of air found on the wing’s surface. Airseas, an Airbus spin-off, said it will install a high-flying towing kite on a bulk carrier by the end of 2021.
After years of development, these wind-driven technologies are taking off as the global maritime industry faces pressure to address climate change. Freight transportation is responsible for nearly 3 percent of the world’s annual greenhouse gas emissions, and ships are a major source of toxic air pollution in ports and coastal communities. For shipping companies, these next-generation sails are a potentially immediate way to reduce emissions, as most systems can be retrofitted to existing ships. And curbing fuel use can lower ships’ operating costs, saving money and avoiding CO2.
Some 15 vessels are currently sailing with wind-assisted propulsion devices, with five more expected by the end of this year. By the end of 2022, the total number could double, to about 40 vessels. That’s a tiny fraction of the world’s roughly 60,000 cargo ships. But it is an important start for an industry that has relied almost exclusively on diesel power for the past century.
Among the current crop of initiatives, WISAMO is the only one that uses inflatable wings. Two Swiss inventors, Edouard Kessi and Laurent de-Kalbermatten, were the first to patent the concept. In 2015, they launched a prototype in a small boat and, two years later, they sailed around Lake Geneva with a 42-square-meter inflatable wing.
Since then, Michelin has improved the original design with new patents, one of which is related to wing inflation, Baisle-Dailliez said. The company now runs real-world simulations and tests on the sailboat in Switzerland, which was provided by French navigator and technical expert Michel Desjoyeaux.
The WISAMO system is designed to operate autonomously, so as not to burden the crew with additional tasks or training requirements. It can also work when the boat is facing the wind, allowing the boat to cover more routes. Baisle-Dailliez said Michelin plans to start testing the wing in the Atlantic Ocean, off the coast of France, starting in September. Regarding the testing of next year’s cargo ship, he said contracts are being signed with potential clients, but they remain confidential.
Demonstrations like these are key to helping wind-assisted propulsion become more widely popular in the global shipping industry. Companies that are wary of investing in novel technologies will look to see if testing can deliver the fuel reductions and the cost savings that developers promise. And regulations that encourage decarbonization, such as taxing CO2 emissions, would also bolster this niche sector, especially if tax dollars were turned into loans or grants to help companies pay for wings, kites or sails, Allwright said. .
