This paper deals with the comparative study of basin type solar stills incorporated with N identical evacuated tubular collectors on the basis of overall energy and exergy for the same basin area under similar climatic condition. In this work, the optimum number of collectors and mass flow rate has been computed followed by the evaluation of annual production of potable water, energy, exergy and production cost of potable water for the proposed systems at 0.14 m water depth for the complex climatic condition of New Delhi. It is inferred that the value of annual energy is higher by 6.85%; annual exergy is higher by 12.30% and production cost of potable water is lower by 15.19% for double slope solar still integrated with N identical evacuated tubular collectors than similar single slope set up. The proposed systems can be used on commercial scale for providing potable water. (C) 2017 Elsevier Ltd. All rights reserved.