Performance enhancement of modified double slope passive solar still using different water-based nanofluids

The aim this study is to analyze the performance of a modified double slope passive solar still (MDSPSS) with and without using water-based nanofluids along with harvesting solar energy. For this, three types of water-based nanofluids used as Aluminum Oxide (Al₂O₃), Zinc Oxide (ZnO) and Copper Oxide (CuO) at different concentrations. This might be an alternative energy source for the existing conventional type of desalination. Consequently, analyzed physical and finalized the suitable water nanofluid for further experimental work. This paper describes a unit which is designed on simple principles of evaporation and condensation with no electricity being used. Thus we harness the heat radiated by the sun to accomplish the evaporation process. After that the condensation process will be start with natural temperature difference between heated and non-heated segment. This modified system with nano-fluid-based as a heat source has made to observed that the effect of different operating modes at climate conditions (month of March 2019) of Lucknow city, India. After experimental result comparison, found that the Aluminum Oxide (Al₂O₃) nanofluid has 36.55% higher productivity and through Copper oxide (CuO) and Zinc Oxide (ZnO), water nanofluid has 15.26% and 21.75% higher production rate respectively concerning still water. The payback period is also calculated for this modified system with nanofluids as 121 days, which is less than that of the unit with normal water. (paper)