Annual thermal performance analysis and economic assessment of an evacuated tube coupled solar still for Indian climatic conditions

In this experimental study, the annual performance and economic analysis of an evacuated tube augmented solar still is presented from June 2020 to May 2021. The experiments are also performed simultaneously on a conventional still as well. The experiments are performed throughout the year at 6 cm water depth for both solar stills in the climate of Kurukshetra City, India. The main output parameters, namely, maximum daily water output, maximum hourly water output, thermal efficiency, and maximum basin water temperature have been taken into account and represented in this study. In addition, thermal analysis for both solar stills is performed in this study. The results from experimentation showed 149% improvement in the daily freshwater output from the modified still in comparison to the conventional still. Also, an increase of 1.7% in overall thermal efficiency is achieved for the modified still in comparison to the conventional still. The maximum still performance is achieved in the month of June 2020. In the economic analysis, the cost of water obtained per litre after distillation is $0.0098 for a conventional still and $0.022 in the case of a modified still.