Meantimes back at the scale I'd prefer to inhabit ~ not least because of its potential ~ the Blue Robotics story is of interest. Guy in LA trashes a surfboard and decides, as you do, to try to sail it to Hawaii under solar power alone. Realises that nobody makes suitable thrusters (motorised props) and finds that there is sufficient latent demand in the wider world to produce the first six hundred in his garage and to sell them on.
Aerial drones are ubiquitous platforms for capturing video, but increasingly they are used for ancillary roles in surveying, inspection and reconnaissance. Aside from me, few people want an FPV powerboat that can be driven from a sofa near the seaside; though there's a burgeoning demand for maritime drones for hydrographic surveys on or under water at a reasonable cost.
The fact is, these things ~ like their airborne associates ~ fulfil roles that previously did not exist, being unaffordable. The model above retails at £5000 here, altogether cheaper than chartering boats and crew.
When it comes to drones then (a) waterways and seas are under-exploited and (b) there's money to be made from successful maritime designs.
Though as with all successful enterprises nowadays, it's best begun as a bit of fun.
