Tubular solar stills: Recent developments and future

Tubular solar still (TSS) has emerged significantly since the last decades for freshwater production especially in small communities and remote areas away from the main infrastructures. In this review, the recent developments, and the future of the various TSS designs and techniques have been discussed in detail. The study covers the parameters affecting the TSS performance concentrating on important achievements and developments in the last ten years with future perspective on the TSS potential in the future desalination market. Moreover, the study analyzed the pre-existing knowledge and highlights the knowledge gaps of the TSS technologies. Results and analysis of this review showed a great potential of the TSS design which still has many opportunities for further development. Some recent TSS applications have been analyzed such as: atmospheric water harvesting (AWH), thermal photovoltage (PVT), recent promising geometries, heat storage materials, and nanomaterials and nanofluids. Moreover, an economic evaluation of the recent TSS technologies has been conducted based on the cost per liter (CPL) of the produced freshwater. At the end, the authors introduced their perspective and outlook on the future of the TSS technologies.