“In this way, the team’s demonstration device can achieve an overall efficiency of 385 percent in converting the energy of sunlight into the energy of water evaporation.”
Stack ten solar stills and let each layer reuse the heat the last one threw away. No pumps, no grid, no membranes to foul. The rooftop prototype makes about 1.5 gallons an hour per square meter. That is a proof of concept, not a water plant, and nobody has shipped one yet.