Abstract The growing demand for sustainable energy and freshwater resources has intensified research into integrated renewable technologies. This study examines the performance of Solar Chimney and Vortex Desalination Power Plants as combined energy desalination solutions. It introduces a novel classification of Solar Chimney and Vortex Air Engine integrated with Desalination Systems based on the mode of air‐water interaction, distinguishing between Direct and Indirect Air‐Water Contact configurations. The study provides a structured foundation to support future development of scalable, sustainable energy desalination solutions. Building on a comprehensive review of experimental and theoretical progress, the study outlines key design strategies, identifies current limitations, and compares different integration approaches. It highlights the potential of these systems to address energy and water challenges, while emphasizing the need for continued innovation to overcome technical and economic barriers.

The shortage of freshwater resources and the depletion of fossil fuels have emerged as two pivotal challenges confronting global development. Photothermal membrane distillation (PMD) technology, a technique that harnesses solar energy for seawater desalination, not only produces freshwater but also mitigates the pressure of energy depletion. However, its sole focus on freshwater production no longer meets the demands of the energy market. Based on this, this study proposes a power–water cogeneration system based on PMD and thermal-osmotic energy conversion (TOEC) technology. The system achieves power–water cogeneration by changing the supply side heat source structure of TOEC technology and coupling it with traditional PMD technology. The experimental results showed that under the illumination condition of solar intensity of 4 kW·m−2 for 3.5 h, the fresh water production and water production rate of the system reached 2.23 g and 1.39 kg·m−2·h−1, respectively. Meanwhile, the fresh water output pressure reached 0.91 bar, and the output power density was 0.0456 W·m−2. This system is expected to provide a new solution to address the global shortage of freshwater resources and the depletion of fossil fuels.

Water scarcity is one of the issues facing Iraq and the world, so finding green ways to desalinate water without harming the environment is one of an important factors. One of these methods is the use of solar energy in water desalination. The traditional solar distillation is one of the successful methods in water desalination, but the productivity of the traditional distillation is somewhat low per square meter, so the productivity of the traditional distillation must be improved. For that reason, a double basin solar still may improve the fresh water output by utilizing the condensation latent heat to heat the water in the upper basin instead of losing it to the atmosphere, as in the case of the conventional solar still. The present work aims to examine the solar still with a double basin for three water depths in the lower basin, 10, 20, and 30 mm, on freshwater productivity and daily efficiency. The still basin area is 400 mm × 1000 mm, with six sub-basins constructed above the first glass cover, each 1 L in volume. The experiments were performed in April 2025 under the climatic conditions of Baghdad, Iraq (Latitude: 33.315° N, Longitude: 44.366° E). The results revealed that the productivity of the double-basin solar still is inversely proportional to the water depth of the lower basin. The maximum water temperature is about 74.5 oC for the lower basin and 71.5 oC for the upper basin at 10 mm water depth. The maximum daily productivity is 6788 ml/m2 at 10 mm water depth. The overall daily efficiency was 72, 70.1, and 62.44 % for 10 mm, 20 mm, and 30 mm water depth. The double basin solar still enhances the distilled water daily for 10 mm water depth by 2.84 % at 20 mm water depth and 14.32% at 30 mm water depth.

The Water-Energy-Food-Ecosystem (WEFE) Nexus framework provides a holistic approach to sustainable resource management, addressing the interdependencies between these sectors to enhance resilience against climate change and resource scarcity. Despite its potential, financing WEFE projects remains a significant challenge due to complex investment structures, long-term payback periods, and difficulties in demonstrating economic returns. This paper explores innovative financing mechanisms, including climate finance, blended finance, and public-private partnerships (PPPs), which are essential for overcoming these financial barriers. It highlights the need for de-risking investment, ensuring regulatory clarity, and integrating standardized financial metrics to attract private-sector engagement. Several successful WEFE financing case studies illustrate the effectiveness of different investment approaches. The Climate Investor Two model, which combines public, private, and donor capital, has successfully supported renewable energy for irrigation, desalination, and water infrastructure projects in climate-vulnerable regions. Similarly, the Noor Ouarzazate Solar Complex in Morocco, a PPP-funded renewable energy and water efficiency project, demonstrates how government-backed risk-sharing mechanisms can mobilize large-scale private investment. Nature-based financial instruments, such as green bonds, resilience bonds, and Payment for Ecosystem Services (PES), have proven effective in promoting sustainable land management and watershed conservation. Despite these advancements, challenges such as fragmented governance, lack of standardized investment criteria, and perceived financial risks continue to hinder widespread WEFE financing. Addressing these gaps requires clear regulatory frameworks, performance-based financial incentives, and integrated risk mitigation mechanisms. This article underscores the critical role of blended finance, insurance-backed risk-sharing, and policy-driven financial incentives in ensuring long-term sustainability and scalability of WEFE projects. By strengthening financial instruments and aligning them with climate resilience and sustainability goals, WEFE investments can drive socioeconomic development while safeguarding essential ecosystem services.

Multifunctional and sustainable chitosan-based interfacial materials for effective water evaporation, desalination, and wastewater purification: A review.

In order to improve the efficiency of high-pressure liquid recovery and utilization in the desalination industry, a forward curved blade turbine in the desalination energy recovery integrated machine is investigated as the research object in this article. The optimization research of the flow components is completed, and the transient pressure pulsation characteristics of the turbine before and after optimization are analyzed. The numerical simulations are performed using Ansys CFX software. The study found that the volute pressure pulsation is mainly affected by the rotor-stator interaction, and its amplitude is proportional to the distance from the impeller. The intensity and range of the pressure fluctuation in the impeller are mainly affected by the flow separation effect, among which the separation vortex and secondary vortex cause low-frequency pulsation in the flow channel. The pressure pulsation amplitude of the optimized geometry is reduced compared with the initial geometry under various operating conditions. The dead water area of the flow field in the impeller flow channel is reduced, and the low work capacity caused by the low pressure on the leading edge pressure surface of the blade under small flow conditions is improved. This enhancement is conducive to increasing the pressure bearing capacity of the blade and reducing the possibility of blade damage due to uneven force. The optimization contributes to the stable operation of the turbine.

With the global push for sustainable solutions to combat climate change and freshwater scarcity, this research investigates a 100% renewable energy-powered combined power and desalination system using solar and wind energy. It addresses existing gaps in studies that often overlook comprehensive optimization and effective dynamic scheduling. Two energy management scenarios─pumped storage alone and a combination of pumped storage and battery integration─were analyzed to evaluate their performance across different seasonal variations and operational conditions. The study’s findings demonstrate that the proposed system achieves a power and water load satisfaction rate exceeding 99%, with energy losses kept below 2%. Incorporating battery storage not only further reduces the total annual operational costs but also enhances economic feasibility and system stability throughout the year. On a typical high-demand summer day, the integrated system achieves significant environmental benefits, saving up to 6.47 tons of coal and reducing CO2 emissions by approximately 16.96 tons. By combining optimization techniques and a comprehensive energy management strategy, this study provides a practical framework for implementing renewable energy-based desalination systems that ensure reliable operation and minimize energy waste, supporting the transition toward sustainable energy and water supply solutions.

This study identifies the optimal location for an offshore energy island to supply sustainable power to desalination plants along the Red Sea coast. As demand for clean energy in water production grows, integrating renewables into desalination systems becomes increasingly essential. A decision-making framework was developed to assess site feasibility based on renewable energy potential (solar, wind, and wave), marine traffic, site suitability, planned developments, and proximity to desalination facilities. Data was sourced from platforms such as Windguru and RETScreen, and spatial analysis was conducted using Inverse Distance Weighting (IDW) and Multi-Criteria Decision Analysis (MCDA). Results indicate that the central Red Sea region offers the most favorable conditions, combining high renewable resource availability with existing infrastructure. The estimated regional desalination energy demand of 2.1 million kW can be met using available renewable sources. Integrating these sources is expected to reduce local CO2 emissions by up to 43.17% and global desalination-related emissions by 9.5%. Spatial constraints for offshore installations were also identified, with land-based solar energy proposed as a complementary solution. The study underscores the need for further research into wave energy potential in the Red Sea, due to limited real-time data and the absence of a dedicated wave energy atlas.

Sustainably harnessing of LNG cold energy for power generation and wastewater desalination

High-performance, salt-resistant, and stable wood-based solar evaporator equipped with sodium alginate-based functional skin.

Utilization of Janus membranes and low-grade thermal energy for sustainable desalination

Interfacial solar-driven evaporation has attracted great research interests, given its high conversion efficiency of solar energy and transformative industrial potential for desalination. However, current evaporators with porous volume remain critical challenges by inherently balancing efficient fluid transport and effective heat localization. Herein, we propose the strategy and design of lightweight, flexible and monolayered fluidic diode membrane-based evaporators, featuring regularly arrayed macropores and dense nanopores on each side. Such a delicate microstructure offers universality in establishing asymmetric channels along macroporous-to-nanoporous to enable the diode-like directional water transport as well as facilitate the heat localization on the nanopores side. Consequently, a high evaporation rate of a maximum 3.82 kg m−2 h−1 can be achieved under 1 sun illumination, exceeding most 2D and 3D evaporators. Besides, the durability and practicability of our evaporators are validated through salt resistance tests, purification experiments among various contaminants, and outdoor evaluations. Moreover, the structure engineering and water-transport optimization of fluidic diode membranes also offer potentials for hydrovoltaic applications, with over 1.6 V generated by tandem devices at the ambient environment. This work provides a concept for designing high-performance monolayered membranes applicable in environmental and energy-related realms.

This study investigates the potential for energy reduction in a full-scale Seawater Reverse Osmosis (SWRO) desalination plant through hybrid integration with Pressure Retarded Osmosis (PRO). A pilot test using a 60 m2 PRO membrane kit helped determine key operating parameters, including draw solution (DS) pressure and resulting dilution fluxes. Subsequently, a full-scale analysis was conducted with 650 m2 of PRO membrane area. The integration demonstrated up to 12.56% reduction in specific energy consumption under optimized conditions. Energy savings were found to correlate positively with lower feed pressures, higher brine availability, and optimal dilution rates, while being negatively impacted by pressure losses and high DS-to-FS flow ratios. The study confirms the viability of PRO-SWRO hybridization as a method for enhancing desalination energy efficiency, and highlights areas for further optimization in membrane design and hydraulic configuration.

Two-Phase flow model-driven optimization of charge percolation in flow-electrode capacitive deionization.

Desalination of sea water projects are critical for addressing water scarcity in regions like Egypt, but they face numerous risks that can hinder their success. This study identifies and analyzes 53 risk factors affecting renewable energy desalination projects through expert interviews, literature review, and a questionnaire survey completed by 47 experts. Statistical methods, including descriptive statistics (mean, mode, standard error, and standard deviation), Pearson correlation, and Cronbach's alpha, were employed to validate the reliability and significance of these factors. The overall questionnaire showed excellent reliability (α = 0.815 for probability of occurrence; α = 0.921 for degree of impact). The results indicate a strong consensus among industry experts. Inflation and price fluctuations was ranked as the highest-probability risk (mean = 4.32/5), while faulty design of plant components (intake, outfall, mechanical systems) was ranked as the highest-impact risk (mean = 4.51/5). Conversely, environmental disasters (earthquakes, floods) showed the lowest probability of occurrence (mean = 1.91/5), and social pressures from entities not directly invested in the project’s success showed the lowest degree of impact (mean = 2.70/5). These statistically validated findings provide project stakeholders with critical insights into the most significant threats to desalination initiatives in Egypt's unique operational context. These findings provide a robust basis for understanding and managing risks in desalination projects, contributing to grow the knowledge on desalination project sustainability and offers actionable insights for stakeholders in Egypt and similar arid regions.

This paper reviews recent advancements in integrated thermoelectric power generation and water desalination technologies, driven by the increasing global demand for electricity and freshwater. The growing population and reliance on fossil fuels for electricity generation pose challenges related to environmental pollution and resource depletion, necessitating the exploration of alternative energy sources and desalination techniques. While thermoelectric generators are capable of converting low-temperature thermal energy into electricity and desalination processes that can utilize low-temperature thermal energy, their effective integration remains largely unexplored. Currently available hybrid power and water systems, such as those combining conventional heat engine cycles (e.g., the Rankine and Kalina cycles) with reverse osmosis, multi-effect distillation, and humidification–dehumidification, are limited in effectively utilizing low-grade thermal energy for simultaneous power generation and desalination, while solid-state heat-to-work conversion technology, such as thermoelectric generators, have low heat-to-work conversion efficiency. This paper identifies a key research gap in the limited effective integration of thermoelectric generators and desalination, despite their complementary characteristics. The study highlights the potential of hybrid systems, which leverage low-grade thermal energy for simultaneous power generation and desalination. The review also explores emerging material innovations in high figure of merit thermoelectric materials and advanced MD membranes, which could significantly enhance system performance. Furthermore, hybrid power–desalination systems incorporating thermoelectric generators with concentrated photovoltaic cells, solar thermal collectors, geothermal energy, and organic Rankine cycles (ORCs) are examined to highlight their potential for sustainable energy and water production. The findings underscore the importance of optimizing material properties, system configurations, and operating conditions to maximize efficiency and output while reducing economic and environmental costs.

Solar desalination shows promise in tackling freshwater shortages, but challenges arise from the trade-off between water transportation and heat supply, affecting evaporators' efficiency and salt resistance. Additionally, intermittent nature of solar radiation significantly diminishes overall evaporative performance. This study presents dual-gradient heating solar evaporator for efficient desalination. Dual-gradient heating is enabled through wettability difference (hydrophilicity aerogel and hydrophobicity film) and difference in phase transition temperature of phase change material, thus, effective heat supply can be provided to evaporation layer consisting of vertically oriented phase-change aerogel by surrounding heating layer consisting of phase-change film, with and without solar radiation. Employing this design, evaporator demonstrates industry-leading comprehensive performance in practical use. Under one sun illumination, evaporation rate achieves 6.84 kgm-2h-1 in 5.0 wt% salinity, with efficiency of 90.9%. In darkness, evaporation rate remains high at 2.61 kgm-2h-1 (30 minutes). Moreover, evaporator exhibits outstanding solar energy storage capacity and long-term stabe evaporative performance and salt resistance for 7-day testing. Furthermore, evaporator successfully produces freshwater from real Bohai Sea water under weak outdoor lighting, addressing recommended daily intake of water for 2.5 households. This work introduces new perspective for maximizing utilization of solar energy for seawater desalination and overcoming intermittent solar radiation.

This study explores the wind energy potential for a wind-powered desalination project in Dakhla, Morocco, by analyzing two models: the Weibull distribution and the WAsP model. Over two years of wind data were processed to estimate energy production, with the Weibull model offering a baseline and the WAsP model refining predictions with site-specific variables. The project, a Public-Private Partnership (PPP), serves 219 agricultural estates over 5200 hectares and ensures potable water for Dakhla’s residents. The PPP framework promotes financial sustainability, with funding shared between public and private stakeholders, ensuring long-term viability in addressing the region’s water-energy needs.

The energy recovery integrated machine can effectively reduce the energy consumption of a seawater desalination system by harnessing the residual pressure energy in high-pressure seawater waste liquid. However, the axial force imbalance between the pump side and the turbine side can lead to axial sliding of the rotor system, and then change the axial clearance size. The objective of this paper is to investigate the unsteady flow pattern in the integrated machine with rotor system axial sliding, focusing specifically on the turbine side under coupled operation conditions. The results show that the increased axial clearance size can lead to the turbine performance decreases obviously but that of the pump side is little affected. The results of entropy production analysis show that impeller, draft tube and volute are core regions of energy loss in the turbine. The flow instability in the impeller, draft tube, and chamber is amplified by the increased axial clearance size, resulting in a greater turbulent kinetic energy dissipation. Unsteady flow phenomena such as jet, flow separation and vortex in the front chamber cause great energy loss. The dominant frequency of pressure fluctuation in the impeller is generally the axial frequency fn. The dominant frequency in the chamber is 6fn. With the increased axial clearance size, the flow instability in the clearance and the front chamber is enhanced. The increased axial clearance size results in the generation of large-scale leakage vortex in the draft tube outlet region. The dominant frequency near the wall of the draft tube gradually changes from 6fn to fn. As the axial clearance size increases, the flow instability in the draft tube is intensified by the gradual increased strength of clearance leakage vortex outside the draft tube.

This study describes a computational model that simulates the behaviour of a solar-powered desalination system. The model incorporates photovoltaic/thermal (PVT) collectors and direct contact membrane distillation (DCMD). A novel DCMD unit model was established and verified using existing data from the literature and the model was incorporated into the TRNSYS library. The effect of feed water mass flow rate and temperature on production was investigated through a parametric analysis. The PVT-DCMD system was modeled, analyzed, and dynamically simulated for the month of June in Algeria using TRNSYS software. Results show that the PVT collector's outlet solar fluid temperature ranges from 20 °C to 85 °C, providing 5000 kJ/hr of useful energy for seawater desalination through a heat exchanger. Meanwhile, the auxiliary heater utilizes around 10,000 kJ/hr of solar energy. The simulation demonstrates the feasibility and effectiveness of using PVT collectors with a DCMD system for seawater desalination, achieving a distillate production rate of approximately 12 L/hr.m2 of membrane.