The advent of sail boats dates back more that 5,000 years, when the ancient Egyptians floated up and down the Nile in wooden vessels powered by wind and oars. Yet, when steam and diesel engines arrived and globalization increased the need for timely trade, sails fell from favor. Today, however, they could be making a comeback as the shipping industry begins to look for greener alternatives.
In mid-September more than 150 leading companies and organizations in shipping, cargo, infrastructure, ports, finance and energy signed a call to action, encouraging world leaders to align shipping with the Paris Agreement goal to keep the increase in global average temperatures from rising above 1.5 degrees Celsius. The International Maritime Organization (IMO) has said it aims to reduce overall greenhouse gas (GHG) emissions from ships by 50% from 2008 levels by 2050, but industry groups are calling for accelerated action for governments.
With about 90% of world trade transported by sea, global shipping accounts for nearly 3% of the world's CO2 emissions, according to the International Maritime Organization (IMO). And with the growing pressure to get cleaner, the question on everyone’s mind is how they will be able to achieve this without significantly cutting profits.
While there have been several different suggestions and trials, earlier this year Michelin announced its wing sail mobility (WISAMO) project which aims to bring sails back to world trade. However, unlike the thick, heavy, laborious sails of the past, Michelin’s inflatable sales are designed to inflate and deflate at the push of a button, meaning no crew is required to rig them. The WISAMO inflatable sales are made from a flexible material that the company have not yet revealed, and they pivot automatically to catch the wind, equipped with sensors that measure the wind direction and speed. This new technology allows them to harness more wind than sails of the past, they are more like the wings of a plane.
The inflatable sales are intended to be fitted onto existing cargo ships, where they will work alongside the ship’s engine, reducing its reliance of fossil fuels. Michelin have estimated that the sails could cut fuel consumption by as much as 20%.
‘The advantage of wind propulsion is that wind energy is clean, free, universal and totally non-controversial,’ said Michel Desjoyaux, world-renowned skipper, and ambassador of the project. ‘It offers a very promising avenue to improving the environmental impact of merchant ships.’
While all this sounds promising, Michelin’s design is still a long way from being used on commercial ships. The company have not yet disclosed if they have secured any contracts with commercial shipping companies and have only test a 1,000 square-foot version of the design on a 40-foot yacht in Switzerland. However, Michelin is not the only company set on bring sails back to the shipping industry. UK-based BAR Technologies has secured a contract with US shipping giant Cargill to retrofit its "WindWings" onto a bulk cargo ship chartered by the company in 2022. Following the same theory BAR Technologies have designed wind wings made of steel that work in the same way as the wings of a plane. Their Wings will sit upright on the deck of a cargo ship and can fold down flat to pass under a bridge or enter a port.
Decarbonization is proving a slow process, with emissions from shipping rising in the last decade. But modern sails could help to accelerate the transition, according to a report released this year from the Institution of Mechanical Engineers. It urged the industry to take up the technology, noting that "21st century wingsails" could play a significant part in reducing the industry's emissions, especially when retrofitted onto existing cargo ships.