Experimental study of a solar water desalination system utilizing evacuated tube heat pipe collector

This paper presents results that were obtained utilizing an evacuated tube heat pipe solar collector, while performing as a solar water desalination system. Data was obtained indoors by the use of a solar simulator (consisting of an array of halogen Flood lights) during experiments conducted in the Department of Mechanical Engineering at Cape Peninsula University of Technology (CPUT). The irradiance from the solar simulator that could be controlled by means of variable transformers varying the voltage to the halogen lamps was measured over the surface of the evacuated heat pipe collector. The procedure allowed for exposure of the collector to the solar simulator for seven hours daily and thereafter normal cooling of the system. Initial testing produced encouraging results. Modifying the system slightly to operate at lowers than atmospheric pressure, evaporation obviously took place at lower temperatures and the amount of potable water harvested increased relative to previous tests.