Interesting. Generally, waterborne freight is far cheaper than rail. Also, at least sometimes you might need to transfer between modes - ship to rail then rail to ship. But with the underwater catenary solution now we're talking about new infrastructure (not to mention R&D, etc.).

As a sort of transitive analysis: Standard waterborne energy costs are included in the superior pricing of waterborne freight compared to rail. If the underwater catenary solution is competitive to standard waterborne energy costs, it beats rail easily. If the underwater catenary is not competitive, it has no value anyway.

It could still have value if we price in, as we should, the externality of GHG output. THe underwater catenary could reduce GHG output in busy waterways by powering boats that don't have batteries.