Experimental and numerical performance analysis and optimization of single slope, double slope and pyramidal shaped solar stills

In this work, the annual performance of single basin single slope, double slope and pyramidal shaped solar stills has been investigated experimentally and theoretically. Experiments were conducted in Ma'an area in Jordan throughout the year from January 2015 to December 2015 on clear days using solar stills with different orientations and different tilt angles of 15°, 30° and 45°. Mathematical models of solar radiation and solar desalination were developed to simulate the availability of solar radiation in Ma'an region, Jordan (Latitude: 30.7 N, Longitude: 35.7 E), and the performance of the solar stills. The average basin area was found to be of 0.64 m2 and 0.82 m2 in January and July, respectively. Model simulations were validated against experimental measurements and a reasonably good agreement was obtained. Annual optimal tilt angles of 30.3°, 45°, and 65° were suggested for south oriented single slope, double slope and pyramidal shaped solar stills, respectively. Under optimal settings, the single slope solar still was found to be the best system with improvement in productivity of about 28%. On a seasonal basis, a south oriented double slope solar still with tilt angle of 35° was found to perform, slightly, better than the other stills in summer.