Enhanced water production in pyramid solar stills: Utilizing suspended trays, fogging system, and forced condensation

This work investigated how to improve the thermal efficiency of pyramid distiller (PSD). A modified PSD (MPSD) was constructed with suspended trays (4-cm width) on three vertical walls. The performance of the MPSD with and without a fogging system was evaluated. Additionally, the MPSD was integrated with an external condensation unit using a withdrawing fan operating at various speeds (1, 1.5, 2, 2.5, 3, & 3.5 rpm). The MPSD with suspended trays exhibited a significant improvement, achieving a 35 % increase in distillate yield compared to the PSD. The MPSD with a fogging system demonstrated a 160 % yield increase. The highest thermal performance for the MPSD with trays, fogger, and external condenser was attained at a fan speed of 2 rpm. At this setting, the MPSD's productivity increased by 194 % with a thermal efficiency of 62.4 %. Notably, the cost of water production decreased from 0.24$/L for the PSD to 0.18$/L for the MPSD. These findings suggest that the MPSD with suspended trays, fogging system, and external condenser offers a promising approach to enhance both the yield and efficiency of solar desalination. •Investigated the performance of a modified pyramid distiller with built-in trays.•Tested the effects of a fogging system and forced condensation.•Achieved 194 % yield rise & 62.4 % efficacy with trays, fogger, and fan at 2 rpm.•Reduced water production cost from $0.24/L (PSD) to $0.18/L (MPSD).