Parametric investigation of a double-effect solar still in comparison with a single-effect solar still Original Research Article

This paper reports the use of two mathematical models to compare the productivity of single-effect and double-effect solar stills under different climatic, design and operational parameters in Oman. The shallow water basin, 23° cover tilt angle, 0.1 m insulation thickness, and asphalt coating of the solar still were found to be the optimum design parameters that produced an average annual solar still yield of 4.15 kg/m2/d and 6 kg/m2/d for single and double effect solar stills, respectively. A cost analysis is carried out to shed some light on the potential of utilizing an array of single-effect solar stills or double-effect solar stills for the production of drinking water in remote areas in Oman. It has been found that the unit cost for distilled water using an array of single-effect solar stills is $74/1000 gal (16.3 $/m3) or $62.4/1000 gal (13.7 $/m3) when using a double-effect solar still. The cost saving is 15.7%.