Investigation on novel design of solar still coupled with two axis solar tracking system

Abstract This work deals with the design, fabrication, and experimentation of an innovative system of solar distillation that uses the concentration effect to increase the heat energy received by the still. So, a modified basin of conventional solar still (CSS) was integrated with a parabolic trough concentrator (PTC) and mounted on an iron structure to form the PTC-CSS. This structure allows the CSS to change continuously its orientation and track the sun from the sunrise to sunset. Also, it allows the permanent meeting of the PTC focal line with the basin absorber. Therefore, the reflected solar rays are directly and continuously concentrated on the water to be distilled with efficiency, and the CSS receives, throughout the day, the maximum solar radiation from two sides i.e. bottom surface and top glass cover. The presented system has allowed the assessment of the continuous direct concentration effect on the absorber of a self-tractable conventional solar still. It was found that the system can ensure a quasi-constant high temperature of water exceeding 80 °C from a low ambient temperature (19-26°C). However, the heat and mass transfer processes that occur inside the still lead to increase considerably the temperature of the glass cover which affects negatively the productivity. Two main experiments were conducted: the first one was to assess the basic performances of the desalination system, whereas the second was performed to give more details about the high temperature of the glass cover revealed during the first experiment. The yield of the presented solar still was about 3.76 l/day. Compared to a compound parabolic concentrator assisted tubular solar still, the yield was slightly increased while the cost investment was reduced by 7%. Also, since the PTC-CSS presents the potential of high level of evaporation, further research focusing on enhancement of the condensation process is expected to give more impressive achievements.