In 2025, a technical and economic study was conducted by Louise Chopinet and Thomas Omnès for Le Caboteur Des Îles, in partnership with the Wind Ship association and ADEME as part of the ReMoVe project. Its aim? To assess the feasibility and potential of sail-powered freight transport in the Bay of Quiberon, serving the islands of Belle-Île, Houat, and Hœdic. This study is part of a broader effort to decarbonise freight transport and shift to more sustainable modes, reducing greenhouse gas emissions and the negative externalities associated with traditional transport.

Why Wind Ship Transport?

An Environmental and Logistical Challenge

The Bay of Quiberon is an island territory where freight transport currently relies mainly on lorries and motorised vessels. However, this dependence on road transport and fossil fuels generates significant environmental and social impacts: CO₂ emissions, air pollution, road congestion, and noise pollution.

Sail-powered transport—using cargo sailing ships—emerges as a promising alternative to reduce these impacts. The study explored several scenarios to assess the economic and energy efficiency of this solution, comparing the performance of sail-powered vessels with conventional ships and optimising the road transport component.

The Scenarios Studied

The study analysed various maritime transport scenarios to Belle-Île and Houat, departing from two mainland ports: Lorient and Kerisper (Saint-Philibert). Three types of vessels were considered:

A 50-tonne cargo sailing ship (similar to Grain de Sail);
A 100-tonne intermediate vessel;
A 350-tonne cargo sailing ship (similar to Grain de Sail 2).

Each scenario was evaluated based on economic, energy, and logistical criteria, such as:

Volume of goods transported;
Investment and operating costs;
Greenhouse gas emissions avoided;
Reduced negative externalities (noise, congestion, etc.).

Significant Environmental Benefits

The study reveals that sail-powered transport significantly reduces greenhouse gas emissions and negative externalities compared to conventional road and maritime transport. For example:

For 6 tonnes transported from Lorient to Belle-Île: up to 70% fewer greenhouse gas emissions (26% fewer negative externalities for road transport and 92% for maritime transport).
For 6 tonnes transported from Lorient to Houat: up to 85% fewer greenhouse gas emissions (29% fewer negative externalities for road transport and 96% for maritime transport).

These results demonstrate that sail-powered transport is not only more environmentally friendly but also more energy-efficient.

Variable Economic Viability Depending on the Scenario

The economic analysis shows that the viability of the scenarios depends on several factors:

The 350-tonne vessel is the most competitive, as it can transport almost all current freight flows. However, it requires significant initial investment and adaptation of port infrastructure.
The 50-tonne vessel is less economically competitive but has the advantage of being quickly deployable and serving as a demonstrator to convince stakeholders.
The 100-tonne vessel offers a good compromise between transport capacity and investment cost, making it a realistic solution for gradual implementation.

Logistical and Regulatory Challenges

The study also highlights the obstacles that need to be overcome to make these scenarios viable:

Port saturation: Current port infrastructure is primarily dedicated to leisure boating, limiting available space for freight transport.
Regulatory constraints: Port access permits and time restrictions (especially during the summer) complicate the operation of sailing vessels.
Need for efficient consolidation: To optimise costs and transport times, it is essential to establish effective consolidation hubs upstream of the ports.

Recommendations for the Future

To promote the development of sail-powered transport in the Bay of Quiberon, the study proposes several courses of action:

Adapt port infrastructure: Reserve dedicated spaces for freight transport and facilitate access to docks for sailing vessels.
Provide financial support to emerging players: Subsidies and public funding are essential to reduce initial investment costs and make tariffs more competitive during the experimental phase.
Encourage vessel sharing: Alternating the use of vessels between several islands (e.g., 4 days for Belle-Île and 1 day for Houat) helps optimise costs and improve profitability.
Conduct large-scale experiments: Pilot projects, such as the one carried out with the Grain de Sail cargo sailing ship in 2024, are crucial for validating assumptions and convincing stakeholders.

Towards a Decarbonised Maritime Logistics System

The study conducted in the Bay of Quiberon demonstrates that sail-powered transport is a viable solution for reducing the environmental impact of freight transport. While logistical and economic challenges remain, the encouraging results pave the way for a gradual transition towards more sustainable maritime logistics.

Le Caboteur Des Îles and its partners show that innovation and collaboration between public and private actors are essential for successful maritime decarbonisation. At a time when decarbonising transport is a major challenge, the Bay of Quiberon could well become a model for other island territories.

For further information:

Contact for Le Caboteur Des Îles: contact[@]lecaboteurdesiles.fr
Discover the initiatives of the Wind Ship association.

Wind Ship Propulsion

Technical and Economic Feasibility Study for Sail-Powered Freight Transport in the Bay of Quiberon (2025)