Indigo, sounds like your friend is about to become a slave. Wise him up, fast.
As for this gigayacht BS the solutions to the problems are simple. 5 years cruising will be accomplished by nuclear (black market), solar & wind power, the live plants will be protected by a retractable lexan solarium, the food supply will be grown below the solarium and of course there will be a giant desalination unit to handle drinking and irrigation water. It's a floating biosphere. Oh yeah, biosphere failed. Well, as long as they can grow enough houch nobody will notice. Then again that might increase apetites beyond capacity. Now there's a problem that needs to be addressed.