4E analysis of productivity and efficiency enhancements in pyramid solar distillation: Innovations in tray design, water heating, and forced condensation integration

This research enhances the thermal efficiency of a pyramid solar distiller (PSD) through 4 E (energy, exergy, economic, and environmental) analysis. The modified distiller (MPSD) features suspended trays on three vertical walls, tested with and without heaters, and various water levels (6.2–49.6 L) in the basin. The study also examined MPSD's performance with an external condenser, aided by a fan operating at different speeds (0.25–1.5 rpm). Results showed that the MPSD, with a water depth of 1 cm and 12.4 L in the basin, achieved a 33 % yield improvement and 50.2 % efficiency. Total productivity of MPSD reached 3755 mL/m² compared to 2820 mL/m² for the PSD. MPSD with heaters produced 6430 mL/m², reflecting a 98.5 % increase. The best performance occurred at 1.25 rpm, with a 133 % productivity increase, 66.5 % thermal efficiency, and 4.58 % exergy efficiency. The water cost was $0.23/L for the MPSD, lower than the PSD's $0.34/L. CO₂ emissions were 30.93–32.23 tons per year for different configurations, and enviroeconomic indicators were 447.46–467.33 annually, depending on the setup.