Solar still distillate enhancement techniques and recent developments

Solar still (SS) technology is one of the economic technologies for the conversion of impure water to pure form. A solar still is a device that mimics the way nature makes rain. A SS has many potential applications from the desalting of seawater to the purification of groundwater. It is a proven technique for the removal of hazardous chemicals such as arsenic, fluoride etc. from water. Solar distillation can become a useful process in rural and remote areas suffering from acute water crisis due to the contamination of groundwater and surface reserves either by natural or by anthmpogenic reasons. This work is a review on various techniques of improving the productivity of a SS that are reported. The work also discusses the working of a conventional SS, water quality obtained and heat transfer mechanism of a SS. The article mainly includes modification of the absorber plate, integration of a condenser, use of reflectors, humidification-dehumidification units, integration of thermal energy storage materials, use of Nanoparticles, photovoltaic thermal (PV/T) module integration and thermoelectric coolers. This paper discusses various systems and puts forward a clear picture of the developments in the field of SS research advancement in the 21st century with mention of few pioneering works.