Abstract: A ceiling fan or ceiling fan includes a body defining an interior passage having an inlet and an outlet provided on the body. The inlet, outlet, and interior passage can be annular. An impeller is mounted within the interior passage and driven by a motor mounted within the body to draw a volume of air through the interior passage from the inlet to the outlet. A movable deflector including an inner angled surface and a lower angled surface is provided at the outlet to direct the airflow in a generally outward or generally downward direction, respectively.

Abstract: The sub-ambient solar desalination system includes a solar pond and a pressure reducing structure. The solar pond is adapted for receiving saltwater and heating the saltwater through direct exposure to solar radiation at atmospheric pressure. The pressure reducing structure is in fluid communication with the solar pond for receiving heated saltwater therefrom. The pressure reducing structure is configured such that pressure of the heated saltwater within a central portion of the pressure reducing structure is at sufficiently reduced sub-ambient pressure to undergo a phase change to produce pure water vapor and a concentrated brine solution. The pressure reducing structure has a vapor outlet for releasing the pure water vapor, which is collected in a fresh water tank and condensed into pure liquid water. The solar pond is in fluid communication with an outlet portion of the pressure reducing structure for recycling the concentrated brine solution back to the solar pond.