• Novel Al₂O₃–Urea–Sugarcane Juice (AUS) ternary nanofluid used in solar distiller • Fractional-order model (α = 0. 2) validated against summer and winter experiments • AUS (15%) SD achieved 5. 08 L/m²•day in summer and 3. 82 L/m²•day in winter • Lowest freshwater cost of 0. 017 /L with 2. 4-year economic payback period • Annual CO₂ mitigation of 612 kg/m² confirmed environmental and economic benefits • Thermal efficiency (54. 32%), lowest freshwater cost (0. 017 /L), and 2. 4-year payback period were demonstrated. The large-scale use of passive solar distillers (SD) is limited by low water productivity and poor energy efficiency. This study proposes a recoverable ternary nanofluid made of sugarcane juice (AUS), urea, and AlO₃ nanoparticles to enhance the thermal, financial, and environmental performance of a single-basin solar distiller. Urea, a nitrogen-rich material, and sugarcane juice, a bio-stabilizer, enhance colloidal stability, reusability, and solar energy absorption across the entire spectrum of solar radiation while also distributing recyclable Al 2 O 3 nanoparticles within saline water. Spectroscopic and XRD studies confirmed the improved photon absorption, the increased heat transport, and the stable heterostructures created during these tests. The average crystallite size was found to be around 50 nm. A fractional-order non-local heat transfer model (α = 0. 2) was developed and verified both empirically and statistically using traditional and non-traditional methods, yielding more accurate results than traditional models and having both good and poor results supported by empirical data. The predicted quantities of fresh water produced per m² per day were 5. 08 L m⁻² day⁻¹ in summer and 3. 82 L m⁻² day⁻¹ in winter, at 15% for AUS, which is an increase of 20. 95% and 23. 23%, respectively, compared to a conventional solar still (CSS). AUS-SD system generated a daily thermal output is 3. 19 kWh/m 2 /day at a minimum water cost of 0. 017/L, with an estimated payback time of 2. 4 years and an energy efficiency of 54. 32%. In terms of potential carbon credits (186. 73) and total carbon sequestration (14. 93 tonnes), the annual CO 2 mitigation was found to be 612 kg/m 2. This suggests that a viable and efficient approach for scalable, sustainable solar desalination technology can be developed by applying recoverable ternary nanofluids with fractional order modeling techniques.
Palaniappan et al. (Sun,) studied this question.