Thermodynamic, sustainability, and ANN ‐based performance assessment of a Cocos nucifera L.–bamboo fiber composite solar still integrated with passive enhancement techniques

The growing shortage of potable water and the contamination of freshwater resources have increased demand for sustainable, energy‐efficient desalination techniques. This research developed and experimentally examined a natural fiber composite (NFC)‐based solar still, fabricated from Cocos nucifera L. and bamboo fibers, for freshwater generation under eight distinct operating conditions. The impact of passive enhancement techniques, such as vertical black cotton wick configurations, charcoal thermal storage, reflector incorporation, lower basin water depth, and dropwise preheated water supply, was assessed for thermal efficiency, exergy efficiency, sustainability metrics, and freshwater productivity. The developed composite material demonstrated low thermal conductivity (0.14–0.31 W/m·K) and excellent water resistance, rendering it suitable for solar distillation applications. Experimental results demonstrated that the system utilizing charcoal, preheated dropwise feeding, and a vertical wick arrangement (E‐7) achieved optimal performance, yielding a maximum of 672 mL/day of freshwater, with a basin water temperature of 66°C and a daily energy efficiency of 18.95%. Exergy and sustainability assessments revealed enhanced thermodynamic efficiency and less irreversibility in modified designs. Artificial Neural Network (ANN) modeling was employed to forecast basin water temperature and freshwater productivity. The developed ANN model demonstrated high predictive accuracy, with R 2 values of 0.988 for water temperature and 0.967 for yield. The distilled water generated by the NFC solar still met the drinking water requirements set by WHO, BIS, and EPA. The findings demonstrate that the proposed NFC solar still, along with passive enhancement approaches and ANN‐based prediction, can function as an environmentally friendly and efficient method for decentralized freshwater production.