I believe (sorry, no references) that R/O Filtration uses something on the order of 1/8Th to 1/10Th the energy that Distillation uses.
Of course, distillation is a proven technology for water disinfection. Systems can be sized for one person, up to community-sized systems. SOLAR
Stills have no moving parts
, relying only on the sun for energy, and should last 20 years or more. The cost of materials to build a single Solar
still might be less than $300.
Notwithstanding, I wouldn't want a 212 degree device on my boat (in the tropics).