In the book, futuristic suits let people live in the desert-but would they really work?As you might guess, Frank Herbert's seminal science-fiction novel Dune takes place in an arid environment. In fact, the fictional planet Arrakis is so strapped for water that the people who inhabit its open deserts wear elaborate full-body water-reclamation systems, called stillsuits, which keep them hydrated and cool. With a well-tuned stillsuit you would lose only a thimbleful of water a day, even in the worst conditions. Or so the story goes.1. The skin-contact layer: The inside layer of the suit is porous and pulls away evaporated perspiration for reclamation.2. The outer layers: The outer layers of the suit "include heat exchange filaments and salt precipitators" to reclaim the salt in sweat.3. Forehead, hands, and feet: The stillsuit covers the forehead, the feet, and the palms of the hands-all areas with a high concentration of sweat glands.4. Kinetic power: The suit is powered by kinetic energy from the body's normal movements-especially breathing.5. Water reclamation from, uh…excrement: As Herbert explains, "urine and feces are processed in the thigh pads." Both are mostly water, so this is possible in theory.6. Face filter: The suit has a face mask with filters over the nose and mouth. The wearer breathes in through the mouth and out through the nose, where moisture from respiration is captured.7. Drink up: Reclaimed water collects in catch pockets. A drinking tube clipped to the neck of the suit provides for an easy drink.
Would it work? Probably not. While the water reclamation is possible in theory, there's an inescapable problem of thermodynamics. In Dune, an ecologist named Liet-Kynes says that the suit allows for a "near normal evaporation process," but it's unclear whether that's possible. If normally sweat evaporates to cool you off, then the suit would need a cooling mechanism to condense the sweat vapor back into a liquid, and it's unlikely the body's normal movements could provide enough power for one. If sweat is wicked away from the skin as a liquid, on the other hand, then the body isn't cooled by its evaporation off the skin, and you would cook in the suit.Illustration by Will Etling