Enhancing pyramid solar still performance using suspended vsteps, reflectors, Peltier cooling, forced condensation, and thermal storing materials

This work aims at enhancing the thermal efficiency of pyramid distiller solar still (PDSS). A modified version (MPDSS) was developed, featuring suspended v-steps on the vertical walls of the distiller. Additionally, the MPDSS was equipped with external reflectors (MPDSS-R) designed to concentrate solar energy, thereby potentially increasing evaporation rates. To further boost the condensation rate, three different methods were implemented and evaluated independently: an external condensation unit integrated with the MPDSS (MPDSS-C), a fixed nano-enhanced thermal storing material (NTSM) within the MPDSS (MPDSS-NTSM), and an installed Peltier device (MPDSS-P). The results indicated that the MPDSS with suspended steps achieved a significant improvement, with a 40% increase in distillate yield over PDSS. MPDSS with reflectors resulted in a 96 % increase in yield. Moreover, integrating a Peltier device with the MPDSS led to a 148 % boost in distillate yield, while the yields increased by 139% and 143 % when utilizing the NTSM and the condenser, respectively. Consequently, the optimal performance for the MPDSS was achieved with the combination of reflectors and the Peltier device, attaining a thermal efficiency of 53.96 % and a 148 % improvement in distillate yield. Also, the thermal efficiency of PDSS, MPDSS, MPDSS-R, MPDSS-C, MPDSS-NTSM, and MPDSS-P was 35.46 %, 42.23 %, 46.77 %, 50.89 %, 48.33 %, and 54.67 %, respectively. While the exergy efficiencies ranged from 3.44 % for the PDSS configuration to 4.87 % for the MPDSS-P configuration. Interestingly, the MPDSS-C configuration achieved an exergy efficiency of 4.64 %. The emissions for MPDSS, MPDSS-R, MPDSS-C, MPDSS-NTSM, and MPDSS-P are estimated at 15.03, 14.62, 14.09, 14.30, and 13.79 tons a year, severally. The enviroeconomic parameters were 218, 212, 204, 207, and 200 a year for MPDSS, MPDSS-R, MPDSS-C, MPDSS-NTSM, and MPDSS-P, respectively. Finally, the water expenses are as follows: $0.343/L for the PDSS, $0.292/L for the MPDSS, $0.220/L for the MPDSS-R, $0.082/L for MPDSS-P, $0.105/L for the MPDSS-C, and $0.114/L for the MPDSSNTSM.