Application of Taguchi design to optimize the operational parameters of pyramid solar still integrated with TiO₂ nanoparticles

Abstract The global community is currently grappling with mounting concerns over the scarcity of fresh water, a situation that has emerged due to a complex interplay of various factors. One viable solution to address this issue is the use of renewable energy-powered water desalination. This study presents a thorough assessment of pyramid solar still (PSS) and its modified versions (MPSS) efficiency, which involves the integration of phase change material (PCM) and nano titanium dioxide (nTiO 2 ) in the solar still. The experiments were conducted simultaneously under identical conditions for both the PSS and the modified still. Assessment of the MPSS was conducted, taking into account various operating parameters, including solar intensity (300–900 W m −2 ), water depth (4–8 cm), water inlet temperature (30 °C–50 °C), and the nTiO 2 concentration (0.5–1.5 wt%). In addition, the Taguchi method was used to pinpoint the factors influencing the efficiency of the solar stills, as well as their respective levels. The signal-to-noise ratio and mean response were employed to identify the ideal levels of these parameters. Furthermore, the ANOVA method was utilized to assess the important factors and their impact on the overall production. Additionally, the regression method was employed to examine the type and magnitude of the correlation between the independent variables and the dependent variable. Finally, the estimated optimum production was compared to both the predicted productivity and the actual experimental productivity. An ideal condition was 900 W m −2 intensity of solar radiation, 4 cm depth of water, 50 °C of saline water temperature, and 1 wt% nTiO 2 concentration.