Water scarcity is one of the most critical challenges facing many regions around the world, particularly in arid and semi-arid areas where access to clean water is limited and demand continues to rise. Due to the growing trend in population, industrialization, and climate change, sustainable and low-cost water purification strategies are of urgent need. The use of solar distillation has been identified to be a viable option because it makes use of renewable energy, is easy to operate, and can be decentralized. Traditional solar stills are, however less productive and with low thermal efficiency and this has necessitated technological improvement. This paper is a performance analysis of a Corrugated Modified Solar Still (CMSS) designed by incorporating three main improvements, which include rotating corrugated cylinders, cotton wick material, and the use of photovoltaic panels to power electrical heaters. The experiment was carried out through three days during May 2024 with different rotational speeds (0.2, 0.4, and 0.6 rpm) in order to identify the most efficient setup that would lead to the highest freshwater production. The modified design also incorporates a glass cover inclined at 33°, selected in accordance with the geographical latitude of Baghdad to enhance solar incidence and condensate flow efficiency. The results showed that the CMSS significantly outperformed the Conventional Solar Still (CSS) across all tested conditions. The optimal performance was achieved at a cylinder speed of 0.4 rpm, resulting in a cumulative distillate yield of 7465 mL/m²/day, compared to 1822.8 mL/m²/day for the CSS—representing a productivity increase of approximately 320

Solar distillation represents a sustainable solution for freshwater production in water-scarce regions. However, conventional solar stills (CSS) face significant limitations including low productivity rates, substantial heat losses through rear walls, and inefficient utilization of solar radiation. The study integrates three modifications: (1) a water unit (WU) for heat loss reduction, (2) a vertical wick solar still (VWSS) for hot water feeding, and (3) PCM enhanced with silver nanoparticles for thermal storage. The integrated system CSS + WU + VWSS + PCM-Ag was tested against conventional CSS. Results demonstrated that the fully integrated system (CWCSS + WU + VWSS with PCM-Ag) achieved cumulative daily productivity of 13,250 mL/m2, representing a 327% improvement over conventional solar stills producing 3100 mL/m2. The modified system also reduced the cost of distilled water from 0.024 $/L to 0.013 $/L. These findings confirm that integrated modifications combining heat loss reduction, hot water feeding, and thermal storage substantially enhance solar still performance while maintaining economic viability. The study recommends further optimization of nano-enhanced PCM configurations and extended testing under varying climatic conditions.

Solar desalination remains a practical solution for freshwater scarcity, yet the productivity of conventional systems often falls short. This study introduces an enhanced pyramidal solar still (EMPSS) that integrates a 340 mT magnetic field with a low-voltage electric field (12–24 V) to improve evaporation and condensation performance. Two identical units—a conventional pyramid solar still (CPSS) and the modified EMPSS—were tested outdoors under Baghdad’s climatic conditions. The pyramidal geometry, with its wide condensation surface and reduced shading, provided a stable baseline for comparison. Results show that magnetic activation increased the water–glass temperature difference from 4.5 to 7.7 °C and raised the basin temperature to 54.6 °C, yielding a 29.3

This study investigates the performance enhancement of spherical solar stills (SPSS) for water desalination by integrating magnetic nanoparticles, external magnetic fields, and phase change materials (PCM) modified with Fe3O4 nanoparticles. Three primary modifications were implemented: (i) incorporation of eight cylindrical magnetic elements (270 mT each) into the distiller basin, (ii) integration of three electric heaters (30 W each) powered by a 120 W photovoltaic module, and (iii) enhancement of thermal storage using PCM-Fe3O4 composites. Experimental measurements were conducted over identical time periods with results averaged for accuracy. The magnetic configuration achieved a remarkable 56% increase in daily distilled water production (6700 mL center dot m-2 center dot day-1) compared to conventional SPSS (4300 mL center dot m-2 center dot day-1). The magnetic field reduced the surface tension of saline water, lowered the specific heat capacity, improved convective heat transfer, and enhanced heat storage during daytime operation. Temperature differential analysis revealed that glass cover temperatures reached 51 degrees C in the magnetically enhanced system, compared with 49 degrees C in conventional configurations, with corresponding basin water temperatures of 65.5 degrees C and 63 degrees C, respectively. When coupled with PV-powered electrical heating, the basin water temperature increased to 76 degrees C, exceeding the conventional SPSS by approximately 14 degrees C at peak irradiance (13:00 h). The incorporation of electric heaters boosted productivity by 136% with 58% efficiency; PCM integration yielded a 192% productivity gain and 67.6% efficiency; full PV cooling integration delivered a 234% enhancement, with a peak thermal efficiency of 71%. Economic analysis indicates a cost of distilled water of $0.0136/L for the magnetically enhanced system, compared to $0.017/L for conventional SPSS. These findings establish magnetic field-assisted desalination as a promising approach for improving renewable energy-driven water treatment technologies.

This work investigated the influence of various amendments on a pyramid solar still with rotating cylinders (RCPSS) and rotating corrugated cylinders (RCCPSS). We compared distillate yield from the RCPSS with a baseline design (PSS) to assess the effectiveness of each modification. The study explored incorporating reflectors, silver nanoparticle-infused phase change material (PCM-Ag) composites within the cylinders, and a vapor-withdrawing fan with an external condenser. In addition, three electric heaters were fixed on the basin water to raise its temperature. The energy required to run the heaters was captured from a PV system. Also, the effect of covering corrugated cylinders with wick on the performance of the modified still was also studied. The RCCPSS significantly outperformed the PSS, producing 8500 mL/m² of freshwater daily compared to 3100 mL/m², representing a 174% increase in distillate. Additionally, heaters and PCM-Ag composites further enhanced distillate yield by 244% and 365%, respectively. However, the most optimal configuration involved combining a wick, heaters and fan. This setup yielded the highest distillate production (14950 mL/m²), a 382% increase over PSS, and achieved a thermal efficiency of 75%. Finally, the freshwater production cost was lower for the RCPSS with wick, heaters and fan ($0.01/L) compared to the PSS ($0.02/L). The work demonstrates a strong commitment to advancing the United Nations Sustainable Development Goals (SDGs), particularly SDG 6: Clean Water and Sanitation.

This study introduces a novel concave solar still (CNSS) that integrates a vertical zig-zag wick (VCWSS) and silver-enhanced phase change material (PCM-Ag) to overcome the low productivity of conventional solar stills (CSS). The design's novelty lies in its concave basin, which increases the vaporization area by 70% using transparent sidewalls to maximize irradiance capture, coupled with a thermal cascade from the VCWSS for waste heat recovery. Experimental testing under the climatic conditions of Baghdad, Iraq, demonstrated that the CNSS alone produced 7800 mL/m2 center dot day, a 160% enhancement over the CSS (3000 mL/m2 center dot day). Integration of the VCWSS boosted the combined yield to 12,300 mL/m2 center dot day (290% improvement), while the full system with PCMAg achieved an optimal output of 13,650 mL/m2 center dot day, representing a 326% enhancement. Thermal efficiency progressed from 58% for the basic CNSS to 76.4% for the fully integrated system. These performance gains are achieved without increasing the horizontal land footprint relative to a conventional solar still, making the proposed configuration suitable for decentralized installation in land-constrained or rooftop settings in arid regions. However, the practical deployment of the CNSS-VCWSS-PCM-Ag system requires consideration of the additional capital cost of PCM-Ag integration, long-term stability of wick materials, and the dependence on high solar irradiance, which may limit performance in low-insolation climates.

Low freshwater productivity and the intermittent nature of operation remain the major limitations of conventional solar still (SS) desalination systems, restricting their large-scale and long-term applicability despite their simplicity and low environmental impact. This review comprehensively analyzes the role of copper oxide nanoparticles (CuO NPs) as an effective multifunctional enhancement agent for overcoming these limitations. CuO NPs can be used as a nanofluid in the water basin and as a nanocoating on absorber surfaces to enhance the absorption of solar radiation and, consequently, increase evaporation rates and freshwater productivity. CuO NPs can also be employed as an additive for phase change materials (PCMs) to improve heat charging and discharging characteristics and to modify melting and solidification temperatures, thereby extending SS operation for several hours after sunset. The dual application of CuO NPs as a PCM additive and as an absorber surface coating provides up to 80.20% enhancement in freshwater productivity, achieves a thermal efficiency of 63.71%, and reduces the cost per liter of distilled water by up to 75% compared to conventional SSs. CuO NPs have been applied in both passive and active SS configurations, either individually or in hybrid arrangements. This review critically examines the effects of CuO nanofluid concentration, hybrid CuO-based nanofluids with other nanomaterials, and CuO nanocomposites, highlighting the superior performance of CuO NPs compared to alternative nanoparticles in terms of yield, thermal performance, and economic feasibility. In addition to experimental investigations, relevant theoretical and numerical modeling studies are integrated to provide design-oriented insights and optimization pathways for high-performance SSs.

The escalating global water scarcity crisis necessitates innovative solutions for freshwater production. This study introduces a novel multistage cylindrical solar still (MSCYSS) with generated turbulence to enhance desalination efficiency. The MSCYSS incorporates four design modifications: vertically stacked absorber chambers, perforated tubes for water turbulence, a parabolic solar concentrator (PSC), and an exterior condenser with forced vapor extraction. Comparative experiments were conducted between the conventional cylindrical solar still (CYSS) and a MSCYSS under same operating conditions. Experimental finding demonstrated significant productivity improvements: The MSCYSS achieved a 70

ABSTRACT Solar desalination reduces energy use and produces freshwater sustainably, but its productivity is limited and cannot meet rising demand. Thus, solar desalination system improvements are sought to boost water productivity. Waste materials are abundantly available and burden the environment, making them low‐cost enhancers for solar desalination systems. Using them can be a safe and sustainable way to mitigate waste. This paper discusses biowaste, agricultural waste, industrial and metallic waste, textile and composite waste, and waste heat recovery designs for solar desalination systems. Studies from 2010 to 2025 show that interest in using waste materials has grown gradually, with several studies appearing recently. The literature shows that waste‐based enhancements can increase freshwater productivity by 20%–60%, with some configurations improving more than 100% and up to 170% over conventional stills, and thermal and exergy efficiencies by 30%–70%. Many systems show cost per liter reductions of 30%–70% and payback periods of less than one year in the most effective designs. The integration of waste materials and heat into solar desalination machines is a technically feasible, economically viable, and environmentally friendly technique for freshwater production.

This study enhances hemispherical solar still (HSS) desalination performance through a modified design (MAHSS) integrating two synergistic innovations: (1) immersion of high-intensity neodymium magnets (270 mT) inside the distiller chamber to intensify evaporation, and (2) coupling with cubic wicking still for spacial efficiency. A subsurface bed of phase change material (PCM + Ag) provided supplementary thermal regulation. Experimental results demonstrated a MAHSS daily output of 6100 mL/m2 & sdot;day versus 4000 mL/m2 & sdot;day for conventional HSS, representing a 52.5 % productivity increase. The integrated MAHSS-VCWSS-PCM system achieved 12,400 mL/m2 & sdot;day (195 % enhancement over HSS), with PCM technology delivering the most significant gain at 65 % thermal efficiency. Economic analysis yielded freshwater production costs of 0.022 USD/L (HSS) versus 0.012 USD/L (MAHSS with integrated enhancements). Environmentally, MAHSS reduced COQ emissions by 29.16 tons/year, yielding an enviroeconomic parameter (Z ') of 422.8 USD/year.

The yield of the solar still has been increased using a variety of techniques. The condensing surface's temperature has consequently risen, this negatively impacts the speed of condensing. Numerous techniques have been investigated to cool the condensing surface, such as water cooling, air cooling, adding phase-changing material (PCM), or an external condenser with a suction fan. Analysing previous investigations on cooling glass covers using an external condenser or PCM to ascertain which is more effective was the primary objective of this study. Also, this review aims to promote greater innovation in this field by highlighting promising directions for further investigation. The findings of the literature review indicate that cooling glass with a fan and condensing vapor in the feed water tank works better than cooling glass utilizing Nano PCM. Besides, the thermal efficiency ranges resulting from the addition of an external condenser or PCM are 42 %-72.4 % and 50.7 %-65 %, respectively. And the increases in solar still production when PCM or an external condenser is added range from 26 % to 44 % and 25 %-68 %, respectively. Where the lowest expenses per liter of freshwater generated by external condenser or PCM systems are 0.01 $ and 0.011 $, respectively. Consequently, as compared to PCM systems, solar still systems with an external condenser have higher output, better efficiency, and a lower cost per liter of freshwater.

A novel hybrid freshwater production system combining atmospheric water generation and a pyramidal solar still was developed to address potable water scarcity in remote areas by leveraging the waste heat from a thermoelectric cooling unit used to condense ambient air, redirecting that heat to the solar still to boost evaporation while the cooled air stream lowers the still’s glass temperature to enhance condensation. Field experiments in Karbala, Iraq, under both humid vegetation and arid desert conditions, demonstrated that precise automated control of the multi-source system is essential to accommodate dynamic weather conditions and ensure experimental accuracy. Doubling the thermoelectric cooling power from 330 to 660 W reduced the average glass temperature by 28

Recently, the smaller sizes of nanoparticles (1–100 nm) were used in several applications such as biotechnology, engineering, internal combustion engines and medical sciences. Furthermore, the researchers inside scientific community highlighted on using nano additives into the diesel fuel, neat biodiesel or and biodiesel blends to enhance the thermophysical properties of nanofluid, stability aspects, emission characteristics, and combustion behaviour of diesel engine. This article provides overview of the contribution several of nanoparticles in reduce engine emissions and improve the process of combustion when they adding to the oxygenated fuel blends. Different types and concentrations of nanoparticles can be adding to the fuels to improve the fuel properties by enhancing the stability and physical properties of fuel to help the transport sector in meet stringent emission regulations. The impact of nanoparticles addition to the fuels on emissions of nitrogen oxide (NOX) and characteristics of particulate matter (PM) will be focused through collected data from the literatures that have been done along the earlier years. It is obtained that the results from adding nanoparticles to the oxygenated fuels are very encouraging because of multi-improvement in chemical and physical properties of nanofluid such as medium of high reactive for combustion, high surface to volume ratio, heat and mass transport properties. According to the several publications, it is found that the addition of nanoparticles to the renewable fuel blends reduced the emissions of NOX and PM (concentrations and number) than to the absence nano additives into the oxygenated fuels. In contrast, large size of PM produced as proved in several publications with adding nano additives to the oxygenated fuels in comparison with neat fuel blends.

A pyramidal solar still was modified to boost its water production with an external air impeller. This impeller improved condensation by directing airflow over a designated condensing surface. Separate water collection channels were installed for each glass surface to compare productivity. The improvement came from enhanced heat transfer due to increased airflow. Experiments used air velocities ranging from 2 to 8 m/s, with corresponding power consumption of the impeller being 80 W to 200 W. The temperature decrease on the condensing surface was directly linked to the airflow speed. The biggest temperature drop (4.75°C) occurred at 8 am on the unmodified glass, but this coincided with low solar radiation (631 W/m²) leading to low productivity. The most significant productivity increase, particularly in condensation, happened between 10 am and 11 am, with a rise of up to 33%. This improvement is attributed to moderate air temperatures and relatively high solar radiation during that time. Overall, directing airflow over the condensing surface resulted in a single-surface productivity increase of 2.7% to 10.5%. The daily water yield of the modified solar still improved by 1.8% to 7% compared to the unmodified one. However, the thermal efficiency of the modified passive solar still (MPSS) decreased with increasing airflow. It started at 48.5% with 2 m/s airflow (80 W) and dropped to 39.5% at 8 m/s airflow (200 W).

Water scarcity is a growing threat due to population growth, urbanization, and climate change. This problem hinders sustainable development, making innovative solutions crucial distillation, which utilizes solar energy to convert brackish or saline water into clean drinking water, is emerging as a promising approach. While various solar designs exist, identifying the most efficient and cost-effective option for residential and industrial applications remains challenging. This paper presents a comparative analysis, focusing on practical, between the traditional spherical solar still and an improved design incorporating a fan. In June, we conducted our research in Baghdad, Iraq, utilizing real-world temperature and solar radiation data from the Iraqi Meteorological and Seismic Monitoring Authority. The key finding is that including a fan within the solar system still significantly increases production efficiency by 31.8

Solar distillation plays a crucial role in addressing water purification challenges, making it a key technology in sustainable solutions. To enhance the performance of conventional solar distillers (CSD), this study focused on incorporating an absorber panel as an innovative approach. Two solar distillers were designed, manufactured, and subjected to a 10-hour experimental evaluation, measuring variables such as water temperature, glass covering temperature, ambient temperature, and cumulative productivity. The introduction of the absorber plate resulted in a remarkable increase in productivity, with the modified solar distiller (MSD) achieving a 138.68% improvement, from 1311.3 ml/m2.h to 3129.8 ml/m2.h. The adoption of machine learning techniques for forecasting the accumulated productivity of solar distillation systems holds immense importance in enabling precise and efficient predictions rather than long experimental evaluations. To predict cumulative productivity values, three machine learning models were tested, namely, Support Vector Machine (SVM), Decision Tree (DT) and k Nearest Neighbor (kNN). The kNN algorithm exhibited exceptional performance in forecasting cumulative productivity for both conventional and modified solar distillers, demonstrating a determination coefficient of 1.000 and a zero valued coefficient of variation. These findings highlight the promising potential of machine learning in future research endeavors aimed at forecasting solar distiller outputs.