Distillate yield improvement techniques for solar still coupled with evacuated tube collector: a review

Many effective solutions to the problem of freshwater scarcity have been offered by the research community across the globe. Evacuated tube collector (ETC)–aided solar thermal desalination devices have succeeded magnificently in providing drinking water to the general public, especially in solar-rich isolated locations. Furthermore, heat transfer fluid ETC solar water desalination units are a much smarter, novel, and cost-effective solution that does not needed additional power and is well-suited to remote locations with a greater rate of self-sustainability. The efficiency of ETC-assisted solar distillation equipment as well as the essential analytical parameters related to the device and heat transfer fluid are thoroughly examined in this study. Literatures published in the last three decades are keenly reviewed and reported. The key finding reveals that solar still integrated with ETC can produce 3.5 to 4 l of freshwater per m² area with depth varying from 0.01 to 0.03 m. It is discovered that the ETC-assisted solar still has a mean energy efficiency that is around 33% greater than the traditional solar still. When it comes to exergy efficiency, the ETC solar still outperforms conventional stills by 4%. Novel methods adopted for boosting the effectiveness of a solar still combined with ETC are reported for further research.