Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Solar Desalination”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Demand for off-grid desalination technology in small-island communities — Can interfacial solar vapor generation be the answer?

The demand for an off-grid desalination technology and the feasibility of using interfacial solar vapor generation (ISVG) to address the problem were evaluated within the context of Bungin Island. Bungin Island is a small-island community in Indonesia facing water scarcity. By conducting interviews with households there, we found that households located on the exterior portion of the island faced the greatest challenges to water access. For example, only 17% of exterior households had piped water access, whereas 67% central households had piped water access. Similar inequities for exterior households were also found with respect to the cost of getting additional water. Thus, we determined that an off-grid desalination technology is best suited for solving the water access problems for the most vulnerable communities in small islands. Further, ISVG technologies that draw on the radiative energy in sunlight to achieve desalination are promising in increasing water access by offering a floating off-grid devices on water near exterior households, passive operation, low capital investment, and simple maintenance. These findings stress the importance of understanding how contextual factors shape barriers to water access and provide a road map on how to begin incorporating these factors into the development of a more sustainable desalination technology.

42 ENGINEERING↗
DOE OSTI2023

Temporal performance indicators for an integrated pilot-scale membrane distillation-concentrated solar power/photovoltaic system

Management of concentrate streams in inland applications has uncertain long-term environmental impacts. This study investigates an intensified solar-energy capture desalination system that integrates membrane distillation (MD) with a hybrid concentrated solar power (CSP)/photovoltaic (PV) collector to realize self-sustained zero-waste discharge for effective management of concentrate streams in inland and off-grid applications. The demonstration-scale CSP/PV system can produce up to 178 kWh of thermal energy and 4 kWh of electrical energy per day. The thermal and electrical energy from the CSP/PV system is directly supplied to the air gap MD (AGMD) pilot-scale system producing up to 288 L of distilled water per day. Experiments were performed on the hybrid AGMD-CSP/PV system to evaluate system performance under various operating conditions including AGMD and CSP flow rates, CSP system pre-heating, and AGMD vacuum pressure. Experimental results indicate that doubling the AGMD flow rate results in a 119% increase in thermal energy utilization and a 71% increase in distillate production. Compared to the winter months, operating the system in summer months when direct normal irradiance (DNI) is highest results in nearly double the distillate production (88 L in winter and 168 L in summer) and nearly three times the amount of thermal energy consumption (15 kWh in winter and 43 kWh in summer). Operating with vacuum resulted in a 34% increase in distillate production and allowing the thermal storage reservoir to preheat in the winter resulted in a 61% increase in distillate production. Altogether, experimental results highlight the tradeoff between distillate production and thermal and electrical energy production and consumption under various environmental conditions and the potential for AGMD-CSP/PV to be a stand-alone desalination system.

14 SOLAR ENERGY↗
DOE OSTI2023

Systems and methods for water desalination using thermo-responsive ionic liquids regenerated by solar energy

This disclosure provides systems, methods, and apparatus related to water desalination. In one aspect, a method includes generating a diluted draw solution using forward osmosis. Wastewater is on a first side of an osmotic membrane and a draw solution is on a second side of the osmotic membrane. The draw solution comprises a mixture of water and an ionic liquid. Water in the wastewater diffuses across the osmotic membrane to the draw solution to form the diluted draw solution. The diluted draw solution is heated using a photonic heater to a temperature above a lower critical solution temperature (LCST) of the ionic liquid to phase separate the diluted draw solution into the ionic liquid and treated water.

Kostecki, Robert↗
DOE OSTI2023

Modeling and Optimal Design of a Desalination System Integrated Between a Glass-Covered Solar Collection Water Chamber and a Heat Dissipating Chimney

Abstract Solar thermal energy is trapped in a glass-covered water chamber/basin to provide the heat for evaporation of brackish water in a novel desalination system. To harvest clean water, a chimney is integrated with the water basin, which draws air into the chamber to be humidified by the vapor and then being ventilated via buoyance force. Uniquely, thermal conductive metal sheet is recommended to make the chimney, which allows the vapor in the humid air condenses easily when flowing up. The condensate at the inner wall of the chimney flows down to be collected as clean water. Mathematical modeling and numerical computation have been carried out to delineate the coupling of the buoyance-force-driven flow with the heat and mass transfer of air and water in the solar collection chamber and the condensation of vapor in the heat-dissipating chimney. The objective of the simulation and optimization of the system is to find the best match of the dimensions of the water chamber with a chimney to maximize the production of clean water and energy efficiency. The model has been used to simulation several cases (of water from 40 °C to 50 °C) with available experimental data from the authors’ previous work, and the agreement was satisfactory. The optimization studies found that there is a maximum air flowrate corresponding to a critical chimney height due to the requirement that the chimney is designated to dissipate heat as much as possible to condense water vapor. With the chimney height greater than the critical height, the airflow rate will have a slight decrease. Nevertheless, higher than a critical height is still needed for a chimney to condense more moisture. Optimized chamber diameters at different chimney heights are provided for reference of optimal system designs.

Engineering↗
DOE OSTI2022

Loop Thermosyphon Enhanced Solar Collector

A two-phase loop thermosyphon solar collector was developed to transfer thermal energy efficiently and passively from a concentrated solar collector to a thermal desalination process. The two-phase flow in the loop thermosyphon is driven by a difference in gravitational pressure head between the liquid return line and the two-phase riser located between the evaporator and condenser. A numerical model incorporating mass, energy, and pressure drop balances was developed to predict system performance and use as a design tool. Three iterations of loop thermosyphon solar collectors were designed, fabricated, and tested to validate the numerical analysis and demonstrate system integration. Additionally, a novel solar receiver design was evaluated based on volumetric absorption of the concentrated sunlight by an optically absorptive two-phase working fluid. Life tests were performed to evaluate the working fluid thermal stability and resistance to ultraviolet degradation. A glass receiver tube and associated glass-to-metal junctions were developed. Finally, a full-scale loop thermosyphon was integrated with a parabolic trough solar collector and tested on-sun.

14 SOLAR ENERGY↗
DOE OSTI2024

Energy Where it Matters: Delivering Heat to the Membrane/Water Interface for Enhanced Thermal Desalination

The overall goal of the project is the development of a solar-driven membrane distillation (MD) process that can treat high salinity brines (>100 g/L) at a cost below $1.5/m3. The process relies on thermally and electrically conducting MD membranes that deliver solar heat directly to the membrane surface and prevent membrane fouling through the application of electrical potentials to the membrane surface.

14 SOLAR ENERGY↗
NASA NTRS1979

Solar technology in the Federal Republic of Germany

A series of papers dealing with the status of solar research and development in the Federal Republic of Germany are presented at a conference in Greece with the object of promoting international cooperation in solar energy utilization. The reports focus on solar collector designs, solar systems, heat pumps, solar homes, solar cooling and refrigeration, desalination and electric power generation. Numerous examples of systems produced by German manufacturers are illustrated and described, and performance data are presented.

Source record↗
NASA NTRS1975

Solar stills for agricultural purposes

Basic concepts of using desalinated water for agricultural purposes are outlined. A mathematical model describing heat and mass transfer in a system combining a solar still with a greenhouse, its solution, and test results of a small-scale unit built at the Middle East Technical University, Ankara, Turkey, are discussed. The unit was employed to demonstrate the technical feasibility of the system. Further development and modifications are necessary for larger-scale operations. The basis of an optimization study which is underway at the Brace Research Institute of McGill University in Montreal, Canada, aimed at finding the best combination of design and operation parameters is also presented.

Selcuk, M. K.↗
DOE OSTI2021

Interfacial Solar Evaporation by a 3D Graphene Oxide Stalk for Highly Concentrated Brine Treatment

In this study, we demonstrate a 3-dimensional graphene oxide (3D GO) stalk that operates near the capillary wicking limit to achieve an evaporation flux of 34.7 kg m -2 h -1 under 1 sun conditions (1 kW/m 2 ). This flux represents nearly a 100 times enhancement over a conventional solar evaporation pond. Interfacial solar evaporation traditionally uses 2D evaporators to vaporize water using sunlight, but their low evaporative water flux limits their practical applicability for desalination. Some recent studies using 3D evaporators demonstrate potential for more efficient water transfer, but the flux improvement has been marginal because of a low evaporation area index (EAI), which is defined as the ratio of the total evaporative surface area to the projected ground area. By using a 3D GO stalk with an ultrahigh EAI of 70, we achieved nearly a 20-fold enhancement over a 2D GO evaporator. The 3D GO stalk also exhibited additional advantages including omnidirectional sunlight utilization, a high evaporation flux under dark conditions from more efficient utilization of ambient heating, a dramatic increase of the evaporation rate by introducing wind, and scaling resistance in evaporating brines with a salt content of up to 17.5 wt %. This performance makes the 3D GO stalk well suited for the development of a low-cost, reduced footprint technology for zero liquid discharge in brine management applications.

3D evaporator↗
DOE OSTI2025

Technical, Economic, Energetic, and Environmental Evaluation of Pretreatment Strategies for Scaling Control in Brackish Water Desalination Brine Treatment

Effective pretreatment is essential for achieving long-term stable operation and high water recovery during the desalination of alternative waters. This study developed a process modeling approach for technical, economic, energetic, and environmental assessments of pretreatment technologies to identify the impacts of each technology treating brackish water desalination brine with high scaling propensity. The model simulations evaluated individual pretreatment technologies, including chemical softening (CS), chemical coagulation (CC), electrocoagulation (EC), and ion exchange (IX). In addition, combinations of these pretreatment technologies aiming at the effective reduction of key scaling constituents such as hardness and silica were investigated. The three evaluation parameters in this assessment consist of levelized cost of water (LCOW, $/m 3 ), specific energy consumption and cumulative energy demand (SEC|CED, kWh/m 3 ), and carbon dioxide emissions (CO 2 , kg CO 2-eq /m 3 ). The case study evaluated in this work was the desalination brine from the Kay Bailey Hutchison Desalination Plant (KBHDP) with a total dissolved solids (TDS) concentration of 11,000 mg/L and rich in hardness and silica. The evaluation of individual pretreatment units from the highest to lowest LCOW, SEC|CED, and CO 2 emissions in the KBHDP brine was IX > CS > EC > CC, CS > IX > EC > CC, and CC > CS > EC > IX, respectively. In the case of pretreatment combinations for the KBHDP, the EC + IX treatment combination was shown to be the best in terms of the LCOW and CO 2 emissions. The modeling and evaluation of these pretreatment units provide valuable guidance on the selection of cost-effective, energy-efficient, and environmentally sustainable pretreatment technologies tailored to desalination brine applications for minimal- or zero-liquid discharge.

14 SOLAR ENERGY↗
DOE OSTI2025

A buffering heat exchanger/thermal energy storage system for desalination applications

A buffering heat exchanger/thermal energy storage (BHXTES) system was designed using a fast-response phase-change material/graphite foam (PCM/GF) medium for desalination and potentially other industrial applications. Unlike a store-now-and-use-later TES system, this study focused on developing a dynamically balanced, continuously used, system that optimized three functions. A lab-scale prototype was designed and fabricated with a PureTemp 151/GF storage medium. The experimental data showed excellent thermal performance repeatability indicating minimal effects of PCM expansion and contraction on the GF as well as negligible PCM redistribution effects. The experimental data also served as a validation of the numerical model of the BHXTES system, after which optimization of the BHXTES system was conducted through numerical simulations for both PureTemp 151/GF and solar salt/GF as the storage medium. The results show that, with a Therminol 55 heat transfer fluid, continuous operation of the system can be realized with a solar energy source through cycles of 8-h changing for desalination and energy storage with the supplied heat followed by 16-h discharging for desalination with the stored energy. As a result, the working fluid outlet temperatures are generally in the ranges of approximately 128–160 °C for a PureTemp 151/GF medium and 198–220 °C for a solar salt/GF medium.

Buffering↗
DOE OSTI2026

SIRENOpt.jl

SAND2026-22945O SIRENOpt.jl is a Julia software package for prototype hybrid power, storage, and platform dynamics. It integrates solar, wind, wave, hydrokinetic, diesel, generator, converter, battery, hydrogen, desalination, mooring, and floating-platform model interfaces in an automatic-differentiation-friendly simulation framework. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Michelen Strofer, Carlos [Sandia National Lab. (SN↗
DOE OSTI2025

De-Risking High-Recovery Brackish Water Desalination via Flow Reversal and Feed Flushing Using Techno-Economic Assessment

Novel desalination technologies have demonstrated enhanced performance and improved financial metrics over existing processes adopted by industry. Establishing quantitative performance targets is essential for achieving financial benefits over the current state of the art. Herein, we demonstrate how WaterTAP, a techno-economic assessment (TEA) tool, can be used to identify minimum performance metrics necessary to achieve financial benefit over using existing processes. This study evaluates the feasibility of increasing water recovery at the Chino Desalter I above 90 % through the addition of a third variable configuration reverse osmosis (VCRO) stage. Sensitivity analyses revealed flow reversal frequency, feed flushing volume (used as a cleaning step), and membrane lifespan are key factors influencing the financial viability of the VCRO process. The TEA analysis demonstrated that the system must achieve a recovery of 84 % and a 1-year membrane lifespan to have a breakeven LCOW, while achieving 90 % recovery can ultimately reduce the LCOW by 16 %. Notably, a trade-off between decreasing frictional losses and increased osmotic pressure across the recovery range, resulted in a stable specific energy consumption across the recovery range, enabling meaningful LCOW reductions without an energy penalty, a key finding that contrasts with conventional RO. This work demonstrates how TEA can guide system design by identifying key performance targets and exploring trade-offs, enabling data-driven decisions to de-risk innovative processes. These findings underscore the importance of leveraging TEA to evaluate scaling mitigation strategies and optimize inland desalination systems for sustainable and cost-effective operation.

14 SOLAR ENERGY↗
DOE OSTI2023

Integrated Modeling and Optimal Operation of Multi-Energy System for Coastal Community

Focusing on remote, isolated, and underserved communities, a multi-energy system is designed in this research which is capable of utilizing different energy sources in a more coordinated and energy-efficient way to support various demands, such as fresh water, electricity, hydrogen, thermal demand, etc. The energy sources considered are renewables (wind, solar, marine) and natural gas. The energy conversion process includes water desalination, gas combustion, water electrolyzation, and different types of storage (hydrogen tank, electricity, thermal, etc.) are designed to serve as buffers in supply-demand balancing. Sets of experiments are designed to demonstrate the effectiveness of the proposed operating model and investigate the impact of uncertainties from renewable generations and demands.

Chen, Yang↗
DOE OSTI2022

Transpiration-powered desalination water bottle

Inspired by mangrove trees, we present a theoretical design and analysis of a portable desalinating water bottle powered by transpiration. The bottle includes an annular fin for absorbing solar heat, which is used to boost the evaporation rate of water from the interior synthetic leaf. This synthetic leaf comprises a nanoporous film deposited atop a supporting micromesh. Water evaporating from the leaf generates a highly negative Laplace pressure, which pulls the overlying source water across an upstream reverse osmosis membrane. Evaporated water is re-condensed in the bottom of the bottle for collection. The benefit of our hybrid approach to desalination is that reverse osmosis is spontaneously enabled by transpiration, while the thermal evaporation process is enhanced by heat localization and made more durable by pre-filtering the salt. Finally, we estimate that a 9.4 cm diameter bottle, with a 10 cm wide annular fin, could harvest about a liter of fresh water per day from ocean water.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Comparative techno-economic assessment of osmotically-assisted reverse osmosis and batch-operated vacuum-air-gap membrane distillation for high-salinity water desalination

New developments in pressure- and thermally driven membrane desalination technologies offer the potential to cost-effectively treat high-salinity waters, especially when powered by low-cost solar electricity and thermal energy. This paper presents a comparative techno-economic assessment of the state-of-the-art most promising pressure- and thermally driven membrane technologies for high recovery desalination, namely, osmotically-assisted reverse osmosis (OARO) and batch-operated vacuum-air-gap membrane distillation (batch V-AGMD), to produce potable water while concentrating brine within the range of 140–290 g/L TDS for minimum-liquid-discharge (MLD) and zero-liquid-discharge (ZLD) applications. It is shown that both OARO and batch V-AGMD can treat feedwater and brines with TDS in the range of 30–125 g/L with corresponding fresh water recovery rates of 85–25%. When low cost solar electricity and thermal energy are used, the resulting levelized cost of water (LCOW) from OARO is in the range of 0.70–6.28 $/m 3 , and that from batch-V-AGMD is in the range of 1.74–2.77 $/m 3 . OARO is more cost-effective than batch V-AGMD when feedwater salinity is below 70 g/L and recovery below 75%, whereas batch V-AGMD is more cost-effective at higher recovery rates and salinity levels. Finally, the sensitivity of this comparison on energy prices and module costs is discussed.

42 ENGINEERING↗
DOE OSTI2022

Can Food–Energy–Water Nexus Research Keep Pace with Agricultural Innovation?

The interconnection among food–energy–water (FEW) systems in meeting societal demands is broadly acknowledged. Similarly, competitive or synergistic allocations of water and energy resources for agricultural production, manufacturing, and human consumption are understood, and their economic impacts can be predicted. Far less appreciated and understood are the outcomes of the FEW nexus in response to operation changes in agricultural practices and the associated technological innovations for future generations. Also, the inter-scale and feedback effects of emerging technology-driven resource reallocation and decision-making on FEW systems are largely unknown. For example, how do the agroeconomic feedbacks of intelligent technologies influence the FEW nexus of agricultural production under environmental and demographic changes? How does the necessary water allocation for powering non-powered dams and pumped-storage hydropower generation influence agricultural production and municipal water supply maintenance? How do solar and wind energy farms influence land use for agriculture and the rural economy? In turn, how can the generated solar and wind energy help reduce the cost of groundwater extraction or water desalination?

42 ENGINEERING↗