Synergistic enhancement of hemispherical solar stills: magnetic field application, vertical Wick integration, and nano-enhanced PCM
Fadl A. Essa, Ali Basem, Shaaban M. Shaaban, Suha A. Mohammed, Wissam H. Alawee, A.S. Abdullah, Z.M. Omara
Abstract
This study enhances hemispherical solar still (HSS) desalination performance through a modified design (MAHSS) integrating two synergistic innovations: (1) immersion of high-intensity neodymium magnets (270 mT) inside the distiller chamber to intensify evaporation, and (2) coupling with cubic wicking still for spacial efficiency. A subsurface bed of phase change material (PCM + Ag) provided supplementary thermal regulation. Experimental results demonstrated a MAHSS daily output of 6100 mL/m 2 ·day versus 4000 mL/m 2 ·day for conventional HSS, representing a 52.5 % productivity increase. The integrated MAHSS-VCWSS-PCM system achieved 12,400 mL/m 2 ·day (195 % enhancement over HSS), with PCM technology delivering the most significant gain at 65 % thermal efficiency. Economic analysis yielded freshwater production costs of 0.022 USD/L (HSS) versus 0.012 USD/L (MAHSS with integrated enhancements). Environmentally, MAHSS reduced CO₂ emissions by 29.16 tons/year, yielding an enviroeconomic parameter (Z′) of 422.8 USD/year.