Yep, supporting the moment from the wing via containers is the biggest structural concern. The containers are strong enough in most sea states, with reefing/feathering required in heavier winds and seas. We will stow the sail long before it encounters conditions like the ones shown in your video.

Oceanbird is awesome! The trouble is that overhauling the entire industry with new-built ships would take too long to make a meaningful climate impact, and be extremely expensive (not to mention that their approach only works for ro-ros).

Synthetic fuels will compete with aviation for the green hydrogen supply (needed to make methanol/ammonia/green hydrocarbons) and are expected to cost 2-3x what current fuels cost. This net makes our fuel cost savings case even stronger.

Industry insiders generally already know that there's really no good cost-saving decarbonization solution, and that decarbonizing fast is a hair-on-fire problem for owner/operators. The barriers standing in the way of most wind-assist devices are: poor ROI, shipyard availability for retrofits, risk to shipwoner (capital upfront), and that they don't package on containerships. We solve all these problems by using a large, efficient wing and depending on the container load path. There are technical problems to solve, but the fundamental physics works.