This was the concept behind the OrbSys Shower -- a high-tech purification system that recycles water while you wash. In the eyes of Mahdjoubi, we should start doing it now, before it becomes a necessity.
So how does it work? Similar to space showers, it works on a "closed loop system:" hot water falls from the tap to the drain and is instantly purified to drinking water standard and then pumped back out of the showerhead. As the process is quick, the water remains hot and only needs to be reheated very slightly.
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