Transportation & Logistics Analysis

Pros and cons of sail-powered container ships

September 29 2022

France is one of the countries pioneering sail-powered container shipping projects. The global energy crisis is generating increased interest in what seemed at first to be just a romantic dream.

Photo credit: © Zephyr et Boree

International shipping represents only 2.5% of global greenhouse gas emissions. The sector must, nevertheless, play its part in the efforts under way to fight against global warming and, therefore, start decarbonising. In recent years, there has been a clear revival of interest in a renewable energy form which is as old as it is largely neglected - wind power.

Several projects have been started and France has been very active in this field. Shippers have well understood that the energy transition is not optional. The French shippers' association, the AUTF, has taken strong action to support the new projects via its members looking to take part in eco-responsible projects which markedly reduce the carbon footprint of goods transported.

The global energy crisis we are currently going through has further strengthened interest for such a long-term approach and several projects have now come to maturity. We do not claim here to compile an exhaustive list of such projects but rather to evaluate the issues and challenges which have emerged so far.

Main propulsion source or back-up?

The breakdown below enables us to classify the different kinds of projects.

  • In the transatlantic trades, thanks to favourable currents and winds for a large part of the year, using the wind as a principal propulsion source makes sense when it is coupled with the least polluting auxiliary thermal/electric systems possible.

  • On the major transpacific and Asia/Europe routes, the situation is more complex, since wind powder is intrinsically difficult to square with the idea of regular services. On the other hand, the use of wind as a secondary source of propulsion in certain sailing conditions can in theory reduce classical fuel consumption by 10-20% on deep sea round trips.

Among the secondary forms of propulsion, kite-style technology, using a purpose-built mast system on ships' bows, has been well-tested and works so long as a vessel is not sailing into the wind. Manoeuvring and adjusting the kite remains problematic, since these activities are little automatised and require crews, who are already busy with their conventional sailing duties, to be specially trained. Also, sailings conditions need to be favourable for at least five or six hours to make it worthwhile making use of kite systems.

"Roro" or just Ro…mantic ?

Ro-ro ships seem to be the favourite among the projects in competition because of their flexibility of operation, relatively uncluttered decks, shallow draughts and generally smaller size, which allows quayside operations to be optimised in ports which are increasingly saturated.

The modern clipper concept offers an unbeatable low carbon performance, which can be use for public relations purposes. It does have one major disadvantage, however. Transport capacity is relatively small, particularly for full containers, which are necessarily on trailers. Even with the low transatlantic freight rates currently applying, wind-powered clippers cannot be shown to be profitable at this point.

  • Neoline

Among the most advanced, sail-powered cargo ship projects is unquestionably that championed by Neoline. This company, which was set up in 2015, aims to launch a new regular transatlantic line between Saint-Nazaire in France and the Canadian and US ports of Halifax and Baltimore, with inward and outward calls, too, in the French overseas territory of St-Pierre-et-Miquelon. The line will be served by two ships, allowing for two sailings per month. Each Neoliner will have a capacity of 280 TEU.

The company has backing from major shipper-partners. Despite prestigious references and an operational concept backed by recognised professionals, the company has been struggling during the last two years to get the project off the ground. In May 2022, the Sogestran group, which took a capital stake in the company in 2020, announced that it was withdrawing from the project and the banks, which had been consulted about financing the construction of the company's first two ships, subsequently became more reticent about proceeding.

  • Zephyr et Boree

Another French company which is involved in a number of shipping decarbonisation projects is Zephyr et Boree. The company claims it can carry out projects from beginning to end, from need analysis to ship operation.

In 2019, along with French marine contractor Jifmar, Zephyr et Boree won a tender call for the transportation of sections of the Ariane space launcher to French Guiana. The Canopee, a 121-metre ro-ro ship with four articulated sails, is due to come into service in late 2022 and to make its first voyages to French Guyana in 2023.

Zéphyr et Borée is also active in the container transport field, thanks to active support from shippers. It won a tender call issued by an association of French shippers supporting decarbonised shipping, set up under the aegis of France Supply Chain and the AUTF. The project involves setting up two weekly transatlantic lines between Europe and North America, starting in 2024, using container ships which will be mainly wind-powered. Zephyr et Boree proposes operating 10-12 600 TEU vessels, putting the project on an industrial scale from the start and promising to really compete on rates with existing carbon-powered services. That said, the tender call is only a first stage and shippers will now need to commit themselves formally if the project is really to be realised. Money is the key factor and, as things stand, there is only one CMA CGM and it has recently opted to support a rival project.

Finding financing

CMA CGM, which has already been called to the rescue in the difficult Gefco and Air France affairs, has recently been called in again to play white knight. The group announced in early September 2022 that it had taken a stake in Neoline. The big, family-owned group, which needs no presentation these days, has perhaps here signed off one of its last significant investment projects before it feels the impact of the freight rate boomerang which is starting to affect the shipping market.

It is good news for Neoline, which can pursue its passionate adventure and get a chance to prove its claim to be able to provide an efficient and ecologically virtuous service, with greater certainty that it will be able to build its first ship quickly. It is also courageous of CMA CGM, given that the long-term profitability of the project has still to be proven. But it is also a very clever political move on its part.

  • The project provides fresh support for the French merchant navy officer and ratings training programme, which serves the interests of the wider CMA CGM fleet.
  • It is a perfect promotional tool for finding new talent ready to embark on a career in shipping, particularly among young aspirants who feared they could be stigmatised for working in a sector reputed to care little for good environmental practice.
  • The Saint-Nazaire-Baltimore service, with its calls in Saint-Pierre-et-Miquelon, would create a new link between mainland France and the overseas territory, which is a big plus in terms of territorial transport linksThe company marks points as a result for its patriotism.

Will France's wind-powered propulsion pioneers be able to obtain support from other leading groups? Some of the latter are looking at the question, in any case. The Michelin group is helping the sector, on the one hand as one of the shippers backing Neoline and, on the other, by getting its research and development service to design an inflatable, retractable and automatically operated wing.

These projects are perhaps receiving excessive attention in relations to their real commerical potential but why should we condemn them at this early stage? It is certain that there will be a lot to learn from these wind-power laboratories and that these innovative technical initiatives deserve to be supported as a matter of principle. Let us wish them all the success they deserve, not least because of the way they are highlighting the innovative capacity of the maritime sector.

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Expert in Ocean shipping for 25 years, Jerome puts all his knowledge of the industry to contribution for Upply. Ship captain at heart, he has written the English-French Lexicon of Containerized Shipping (Paris: CELSE, 2001).
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