I live in Portishead (mentioned in this article), we frequently see great barges sail by with massive blocks of concrete destined for HPC. Quite a spectacle to behold!
This is an awesome idea! Whilst I know nothing about containers, I find myself wondering if the connections between containers would be able to support the massive moments of force from these sails. Also, would you have to ensure that all the wings are based at the same height on deck for stability or can that be effectively managed through extending and contracting individual wings? Finally, suppose you need the sail containers to be as close to the deck as possible (anticipating one response to my previous thoughts), how much shipping volume would be sacrificed by being unable to place any containers directly above?