Water scarcity remains a pressing global concern, particularly in dry and semi-dry areas where it is difficult to obtain water that is safe to drink. This experimental study focuses on enhancing the total yield and efficacy of solar still that uses Al2O3– CuO (50:50 ratios) based hybrid nano fluid stored in silver (Ag) cylinder. In this study the impact of basin water depth on total distillate is carried out by comparative analysis of conventional, nano fluid and hybrid nano fluid based solar stills. The experimental values of hybrid nano fluid indicate maximum distillate of 689 ml whereas 605 ml for CuO, 570 ml for Al2O3 and 530 ml for conventional solar still. This illustrates that hybrid nano fluid improves distillate. The performance enhancement of solar still is carried out by using hybrid nano fluid in the context of maximum distillate at basin water depths of 2 cm, 3 cm and 4 cm respectively. The result shows maximum yield 689 ml is obtained at 2 cm water depth for Al2O3 – CuO hybrid nano fluid based solar still at 0.1% concentration which is higher than others such as 598 ml and 488 ml received for 3 cm and 4 cm water depth respectively. Also, thermal energy balance equations and coefficient of heat transfer have been studied for 2 cm, 3 cm and 4 cm water depths. The highest amount of evaporative heat transfer coefficients (hewg) is 32.23 W/m2 K at 2 cm while 23.06 W/m2 K at 3 cm and 12.90 W/m2 K at 4 cm water depth respectively. Due to this reason, high rate of evaporation of basin water takes place and total yield is enhanced at 2 cm water depth. This analysis depicts that Al2O3 – CuO hybrid nano fluid performs more favorable than nano fluid and conventional solar still.
