Download or read book Energy Optimization of Brackish Groundwater Reverse Osmosis Desalination written by John P. MacHarg and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Consumption Optimization of a Brackish Water Reverse Osmosis System written by Leili Abkar and published by . This book was released on 2015 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clean water and energy are two key concerns in today's world, and climate change is making both of these issues even of more significant importance. Desalination, a process that removes salt from saline water to produce fresh water, is a solution for the worsening water scarcity issues. Many different desalination technologies are available and applied around the world, including thermal-based technologies, which include multi-stage flash (MSF) and multiple effect distillation (MED), as well as membrane-based technologies such as reverse osmosis (RO) and also electrodialysis reversal (EDR). Reverse osmosis is the most commonly used membrane-based technology, capable of eliminating a wide range of contaminants to produce clean water. There are two different types of RO systems, Brackish Water Reverse Osmosis (BWRO) and Seawater Reverse Osmosis (SWRO), which are applied based on the characteristics of the feedwater. In inland regions, groundwater, surface water, and river water are considered brackish water. In the state of New Mexico for instance, brackish water is the available feedwater source, and therefore BWRO is applied to provide fresh water. Due to a water shortage crisis in the Southwest USA, one of the major goals is to optimize the BWRO process to minimize energy consumption and simultaneously increase the water recovery rate. By increasing the recovery rate, a higher percentage of the feedwater is converted into fresh water; therefore, less feedwater is required to produce a given quantity of fresh water, conserving water resources. In this research, energy consumption optimization for BWRO systems has been investigated. The key control factors for minimizing BWRO energy consumption include feed flow rate, pressure, and temperature, as operating conditions, feed concentrations, and membrane type (representing membrane permeability). The effect of each of these control factors on energy consumption is evaluated, and presented. A full factorial design has been done with mixed level for different factors. In this research, pressure has six level in the range of 50-175 psi by the 25 psi step, Flow rate 3-6 LPM with the step of 1 LPM, temperature has two level of 30 and 40 centigrade, and salinity varies from 2,000, 2,500, 3,000 ppm to cover the middle range of brackish water. Each experiment has three replication. Using linear regression method makes it possible to determine relation between input variable (feed flowrate, salinity, pressure and temperature) and response variable (energy, recovery and specific energy consumption). The empirical model developed to predict the energy, recovery and specific energy consumption of the reverse osmosis system in the specified range and finding the sweet spot to run the system to produce the minimum energy cost for 1 cubic meter of water.

Download or read book Reverse Osmosis Systems written by Syed Javaid Zaidi and published by Elsevier. This book was released on 2021-12-03 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reverse Osmosis Systems: Design, Optimization and Troubleshooting Guide describes in depth knowledge of designing and operating reverse osmosis (RO) systems for water desalination, and covers issues which will effect the probability for the long-standing success of the application. It also provides guidelines that will increase the performance of seawater RO desalination systems by avoiding errors in the design and operation and suggest corrective measures and troubleshooting of the problems encountered during RO operation. This book also provides guidelines for the best RO design and operational performance. In the introductory section, the book covers the history of RO along with the fundamentals, principles, transport models, and equations. Following sections cover the practical areas such as pretreatment processes, design parameters, design software programs (WAVE, IMSDesign, TORAYDS2, Lewaplus, ROAM Ver. 2.0, Winflows etc.), RO performance monitoring, normalization software programs (RODataXL and TorayTrak), troubleshooting as well as system engineering. Simplified methods to use the design software programs are also properly illustrated and the screenshots of the results, methods etc. are also given here along with a video tutorial.The final section of the book includes the frequently asked questions along with their answers. Moreover, various case studies carried out and recent developments related to RO system performance, membrane fouling, scaling, and degradation studies have been analyzed. The book also has several work out examples, which are detailed in a careful as well as simple manner that help the reader to understand and follow it properly. The information presented in some of the case studies are obtained from existing commercial RO desalination plants. These topics enable the book to become a perfect tool for engineers and plant operators/technicians, who are responsible for RO system design, operation, maintenance, and troubleshooting. With the right system design, proper operation, and maintenance program, the RO system can offer high purity water for several years. - Provides guidelines for the optimum design and operational performance of reverse osmosis desalination plants - Presents step-by-step procedure to design reverse osmosis system with the latest design software programs along with a video tutorial - Analyzes some of the issues faced during the design and operation of the reverse osmosis desalination systems, suggest corrective measures and its troubleshooting - Discusses reverse osmosis desalination pretreatment processes, design parameters, system performance monitoring, and normalization software programs - Examines recent developments related to system performance, membrane fouling, and scaling studies - Presents case studies related to commercial reverse osmosis desalination plants - Perfect training guide for engineers and plant operators, who are responsible for reverse osmosis system design, operation and maintainance

Download or read book Energy efficient Desalination of Brackish Groundwater by Nanofiltration reverse Osmosis Hybrid written by Atefe Hadi and published by . This book was released on 2015 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Desalination can produce freshwater from seawater and brackish water, alleviating the critical issue of freshwater shortages. There are multiple desalination technologies, but membrane-based technologies are used most frequently because of their low cost, low energy comsumption, compactness, and short installation period. Among the membrane-based desalination technologies, reverse osmosis (RO) is most prevalent because of its ability to treat many types of feed water, ease of maintenance, and production of high-quality water. However, compared to some membrane technologies, RO suffers from high energy comsumption, inadequate water recovery, and membrane fouling. As an alternative to RO systems, nanofiltration (NF) membranes have been developed for desalinating moderately or slightly saline water sources such as brackish groundwater. NF has a lower ion rejection rate than RO, but is more energy efficient because of this and is able to operate at higher flux and lower pressures. Despite these known advantages and disadvantages, it has been difficult to directly compare the performances of RO and NF technologies because RO has a higher ion rejection rate while NF has a higher energy efficiency. This impedes the selection of optimal desalination systems for given conditions. To solve this problem, the present study uses the criteria minimized specific energy consumption and acceptable product water quality to compare the performances of RO, NF, and a hybrid NF/RO system in the treatment of brackish groundwater. Using resources at the Brackish Groundwater National Desalination Research Facility (BGNDRF), optimum operating conditions were obtained for all three systems by varying the parameters of feed flow rate, feed concentration, and system recovery. To prevent membrane fouling, appropriate pretreatment methods were applied in all experiments. Results showed that, based on the calculated specific energy consumption and World Health Organization standards for potable water, NF, hybrid NF/RO, and RO systems were best for desalinating low, moderate, and high salinity feed waters, respectively.

Download or read book Sustainable Desalination and Water Reuse written by Eric M.V. Hoek and published by Springer Nature. This book was released on 2022-05-31 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past half century, reverse osmosis (RO) has grown from a nascent niche technology into the most versatile and effective desalination and advanced water treatment technology available. However, there remain certain challenges for improving the cost-effectiveness and sustainability of RO desalination plants in various applications. In low-pressure RO applications, both capital (CAPEX) and operating (OPEX) costs are largely influenced by product water recovery, which is typically limited by mineral scale formation. In seawater applications, recovery tends to be limited by the salinity limits on brine discharge and cost is dominated by energy demand. The combination of water scarcity and sustainability imperatives, in many locations, is driving system designs towards minimal and zero liquid discharge (M/ZLD) for inland brackish water, municipal and industrial wastewaters, and even seawater desalination. Herein, we review the basic principles of RO processes, the state-of-the-art for RO membranes, modules and system designs as well as methods for concentrating and treating brines to achieve MLD/ZLD, resource recovery and renewable energy powered desalination systems. Throughout, we provide examples of installations employing conventional and some novel approaches towards high recovery RO in a range of applications from brackish groundwater desalination to oil and gas produced water treatment and seawater desalination.

Download or read book The Energy water Nexus written by Gary M. Gold and published by . This book was released on 2015 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water stress is a worldwide reality. Planners and managers of water resources around the world are tasked with finding new, creative, and innovative solutions to challenges posed by growing populations and declining water supplies. Securing safe drinking water, however, has impacts beyond the water sector. In particular, the connection between energy and water must be carefully considered to avoid unwelcome increases in energy consumption as a result of new water management strategies. One strategy that is gaining increasing attention is desalination of brackish groundwater. However, desalination is an energy-intensive process and could have negative impacts in the energy sector if conventional approaches are used. Relying on fossil fuels for desalination could drive up carbon dioxide emissions associated with water treatment and increase the cost required to produce drinking water. Integrating desalination with renewable power sources such as wind and so- lar energy can mitigate concerns regarding the energy intensity of desalination. By coupling water treatment with non-carbon emitting sources of power, it is possible to meet growing water demands in a sustainable manner. At the same time, water pro- duction offers an opportunity to address problems associated with the intermittent nature of wind and solar power production. Desalination is a time-flexible process that pairs well with wind and solar power, two sources of energy that are limited in application by their daily and seasonal variability. Integrating desalination with wind and solar power offers a solution to energetic challenges of water production while using wind and solar power for desalination offers a solution to challenges associated with the intermittent nature of renewable power. Additionally, utilizing photovoltaic-thermal (PVT) solar modules in an inte- grated facility could be advantageous to both the water and solar power production processes. Brackish groundwater, which is at a relatively cool temperature, can be used to cool solar panels, which suffer from losses in efficiency associated with tem- perature increases. At the same time, solar panels can be used to preheat feed water, a process that reduces the energetic requirement for reverse osmosis desalination. Us- ing the temperature difference between brackish groundwater and solar panels to an engineering advantage can be beneficial for the production of both solar power and drinking water. This thesis offers an investigation of desalination powered by wind and solar energy, including a study of a configuration using PVT solar panels. First, a water treatment was developed to estimate the power requirement for brackish groundwa- ter reverse-osmosis (BWRO) desalination. Next, an energy model was designed to (1) size a wind farm based on this power requirement and (2) size a solar farm to preheat water before reverse osmosis treatment. Finally, an integrated model was developed that combines results from the water treatment and energy models. The integrated model uses optimization to simulate the performance of the proposed facil- ity by maximizing daily operational profits. Results indicate that integrated facility can reduce grid-purchased electricity costs by 88% during summer months and 89% during winter when compared to a stand-alone desalination plant. Additionally, the model suggests that the integrated configuration can generate $574 during summer and $252 from sales of wind- and solar-generated electricity to supplement revenue from water production. These results indicate that an integrated facility combin- ing desalination, wind power, and solar power can potentially reduce reliance on grid-purchased electricity and advance the use of renewable power. In addition, this analysis fills a knowledge gap in understanding the advantages and tradeoffs between using wind power, solar power, and a combination of wind and solar power for desali- nation. By providing insight into the potential operations of an integrated facility, the investigation discussed in this report aids to the understanding of the water-energy nexus associated with new sources of drinking water. Results from this thesis indicate that integrating desalination with renewable power provides an opportunity for collaboration that can be mutually beneficial to both the water and energy sectors. In particular combining desalination, wind power, and solar power can overcome challenges associated with each of these technologies and may be preferable to stand-alone water or power producing facilities.

Download or read book Renewable Energy Powered Desalination Handbook written by Gnaneswar Gude and published by Butterworth-Heinemann. This book was released on 2018-03-08 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: Renewable Energy Powered Desalination Handbook: Applications and Thermodynamics offers a practical handbook on the use of renewable technologies to produce freshwater using sustainable methods. Sections cover the different renewable technologies currently used in the field, including solar, wind, geothermal and nuclear desalination. This coverage is followed by an equally important clear and rigorous discussion of energy recovery and the thermodynamics of desalination processes. While seawater desalination can provide a climate-independent source of drinking water, the process is energy-intensive and environmentally damaging. This book provides readers with the latest methods, processes, and technologies available for utilizing renewable energy applications as a valuable technology. Desalination based on the use of renewable energy sources can provide a sustainable way to produce fresh water. It is expected to become economically attractive as the costs of renewable technologies continue to decline and the prices of fossil fuels continue to increase. - Covers renewable energy sources, such as nuclear, geothermal, solar and wind powered desalination and energy storage and optimization - Includes energy recovery schemes, optimization and process controls - Elaborates on the principles of thermodynamics and second law efficiencies to improve process performance, including solar desalination - Explains global applicability of solar, wind, geothermal and nuclear energy sources with case studies - Discusses renewable energy-desalinated water optimization schemes for island communities

Download or read book Hybrid Inter stage Design of Brackish Water Reverse Osmosis to Improve Efficiency of Hydraulic Energy written by Masoud Aghajani and published by . This book was released on 2015 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water scarcity and shortage are becoming serious issues for many countries worldwide. These problems inspire new methods of water management and one of common approaches in resource management is increasing production and availability to prevent crisis. Water is not an exception and many sources are considered for this purpose. Water with high concentrations of total dissolved solids (TDS) gradually gained attention of researchers, decision makers and investors. It is mainly thanks to the non-ending seawater source and also saline brackish and surface waters. Reverse Osmosis is the leading technology to desalinate the water and numerous advances have been carried out to more optimize this process. A lot of attention has paid to seawater reverse osmosis and modification and optimization of brackish water reverse osmosis has not been carried out comprehensively. Hybrid membrane inter-stage design (HID) was one of the most recent advancement in seawater reverse osmosis but no report or experimental study has been done on using this novel design for brackish water reverse osmosis. In this study HID design was compared with regular design of brackish water reverse osmosis (BWRO) through experimental work and data collection from a pilot scale reverse osmosis system. Collected data was analyzed through statistical procedures and multiple regression was also carried out on the data to develop predictive models of the system energy consumption. Those models were also used to compare these two different designs of BWRO for recovery rates. Results show that HID design significantly reduces the specific energy consumption of the BWRO system and also at constant energy consumption of the high pressure pump HID designed system can produce more permeate and gives higher recovery rate.

Download or read book Digital Computer Simulation and Optimization of a Reverse Osmosis System for Desalination of Brackish Water written by Gordon Blaine Hatfield and published by . This book was released on 1967 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy and Cost Optimization of Reverse Osmosis Desalination written by Aihua Zhu and published by . This book was released on 2012 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reverse Osmosis Seawater Desalination Volume 2 written by Heinz Ludwig and published by Springer Nature. This book was released on 2022-10-29 with total page 641 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seawater reverse osmosis (SWRO) is the dominant desalination process worldwide for obtaining fresh water from the sea. The subject matter and scope of this book is the conceptual and advanced planning, design and engineering of plants of this desalination process together with the associated facilities for seawater pretreatment, post-treatment of the product water, wastewater treatment, seawater extraction and plant discharge. The book is intended to be used by technicians, engineers, economists and ecologists in the planning, design and operation of SWRO plants, as an educational and training tool, as well as an aid in environmental licensing of membrane desalination plants, and by interested laypersons for information about this process. The two volumes are also available as a set.

Download or read book Geothermal Water Management written by Jochen Bundschuh and published by CRC Press. This book was released on 2018-03-12 with total page 607 pages. Available in PDF, EPUB and Kindle. Book excerpt: Availability of and adequate accessibility to freshwater and energy are two key technological and scientific problems of global significance. At the end of the 20th century, the deficit of water for human consumption and economic application forced us to focus on rational use of resources. Increasing the use of renewable energy sources and improving energy efficiency is a challenge for the 21st century. Geothermal energy is heat energy generated and stored in the Earth, accumulated in hydrothermal systems or in dry rocks within the Earth’s crust, in amounts which constitute the energy resources. The sustainable management of geothermal energy resources should be geared towards optimization of energy recovery, but also towards rational management of water resources since geothermal water serves both as energy carrier and also as valuable raw material. Geothermal waters, depending on their hydrogeothermal characteristics, the lithology of the rocks involved, the depth at which the resources occur and the sources of water supply, may be characterized by very diverse physicochemical parameters. This factor largely determines the technology to be used in their exploitation and the way the geothermal water can be used. This book is focused on the effective use of geothermal water and renewable energy for future needs in order to promote modern, sustainable and effective management of water resources. The research field includes crucial new areas of study: • an improvement in the management of freshwater resources through the use of residual geothermal water; • a review of the technologies available in the field of geothermal water treatment for its (re)use for energetic purposes and freshwater production, and • the development of balneotherapy. The book is aimed at professionals, academics and decision makers worldwide, water sector representatives and administrators, business enterprises specializing in renewable energy management and water treatment, working in the areas of geothermal energy usage, water resources, water supply and energy planning. This book has the potential to become a standard text used by educational institutions and research & development establishments involved in the geothermal water management.

Download or read book Self Adaptive Control of Integrated Ultrafiltration and Reverse Osmosis Desalination Systems written by Larry Xingming Gao and published by . This book was released on 2017 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water shortages in many areas of the world have increased the need for fresh water production through water desalination in applications such as the production of potable water, use in agricultural irrigation, and wastewater reuse. In this regard, reverse osmosis (RO) membrane desalination of both seawater and inland brackish water has emerged as the leading technology for water desalination, with a growing number of large-scale desalination plants in the planning and/or construction stages. Currently, the design of a water desalination plant is typically tailored to the specific water source in terms of meeting productivity targets and pre-treatment requirements. The standard operating procedure is to determine one optimal operating state for an RO system (e.g., overall water recovery, membrane cleaning frequency) and maintain this specific operating point for the duration of operation. However, these methods do not adequately account for the variability in feed water salinity and fouling propensity, and may result in suboptimal operation with respect to excessive energy consumption, poor RO feed pre-treatment, and degradation of RO membrane performance. Therefore, it is crucial to develop effective process control approaches which can mitigate membrane fouling and reduce RO energy consumption in order to improve the robustness of the RO desalination process. In order to reduce membrane fouling, several concepts which involve improvements to RO plant pre-filtration capability (e.g., the addition of a separate, modular ultrafiltration membrane process, the use of a transient high-flux "pulse" backwash) were developed. The concept of direct integration of ultrafiltration (UF) and RO was introduced, whereby the UF filtrate is fed directly to the RO and the RO concentrate is used for UF backwash. Additionally, a control system was designed for the UF pre-treatment unit whereby membrane fouling was reduced through optimization of backwash through a combination of varying the backwash frequency and varying the coagulant dose. This approach was shown to significantly reduce membrane fouling and significantly increased operation duration before chemical cleaning was required (~900% longer). In order to reduce energy consumption of RO desalination, energy-optimal control systems featuring a novel two-layered controller architecture were developed and implemented using fundamental models of specific energy consumption (SEC) of single-stage and two-stage RO systems. The implemented control algorithms utilized extensive sensor measurements from the pilot plants (i.e., flow rate, pressure, conductivity, etc.) to determine the optimal operating set-points for the RO systems (e.g., system feed flow rate, system feed pressure, and overall system water recovery). Accordingly, the control system shifted the RO system operation to the operating conditions that resulted in the lowest energy consumption for a given feed salinity and for a given target product water productivity while accounting for system constraints. The control and design concepts developed in this dissertation were tested on two water purification systems, constructed by a team at UCLA. The two pilot plants were the Smart Integrated Membrane System - Seawater (SIMS-SW) and the Smart Integrated Membrane System - Brackish Water (SIMS-BW). Field tests of the control systems were conducted and the results successfully demonstrated the ability for the control systems presented in this dissertation to reduce membrane fouling and RO energy consumption.

Download or read book Wastewater Treatment by Reverse Osmosis Process written by Mudhar Al-Obaidi and published by CRC Press. This book was released on 2020-02-25 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wastewater Treatment by Reverse Osmosis Process provides a one-stop-shop for reverse osmosis (RO), outlining its scope and limitations for the removal of organic compounds from wastewater. This book covers the state-of-the-art on RO processes and describes ten RO process models of different features and complexities. It also covers the advanced model-based techniques for RO process operations, including various rigorous methods for process modelling, simulation, and optimization at the lowest energy cost, as well as advanced tools such as genetic algorithms for achieving the same. • Highlights different types of physico–chemical and biological wastewater treatment methods including hybrid systems • Provides an overview of membrane processes, focuses on different types of membrane processes for water treatment and explains characteristics of membrane modules • Introduces the importance and challenges of process modelling for simulation, design, and optimization and offers examples across various industries •Describes the concept of different types of genetic algorithms for process optimisation and provides the state-of-the art of the GA method in terms of its application in water desalination and wastewater treatment •Emphasizes economic aspects of RO processes for wastewater treatment With its focus on the challenges posed by an increasing demand for fresh water and the urgent need to recycle wastewater at minimum cost, this work is an invaluable resource for engineers and scientists working within the field of wastewater treatment.

Download or read book Emerging Contaminants Vol 2 written by Nadia Morin-Crini and published by Springer Nature. This book was released on 2021-04-28 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emerging contaminants are chemical and biological agents for which there is growing concern about their potential health and environmental effects. The threat lies in the fact that the sources, fate and toxicology of most of these compounds have not yet been studied. Emerging contaminants, therefore, include a large number of both recently discovered and well-known compounds such as rare earth elements, viruses, bacteria, nanomaterials, microplastics, pharmaceuticals, endocrine disruptors, hormones, personal care products, cosmetics, pesticides, surfactants and industrial chemicals. Emerging contaminants have been found in many daily products, and some of them accumulate in the food chain. Correlations have been observed between aquatic pollution by emerging contaminants and discharges from wastewater treatment plants. Most actual remediation methods are not effective at removing emerging contaminants. This second volume presents comprehensive knowledge on emerging contaminants with a focus on remediation.

Download or read book Improving Recovery in Reverse Osmosis Desalination of Inland Brackish Groundwaters Via Electrodialysis written by William Shane Walker and published by . This book was released on 2010 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: As freshwater resources are limited and stressed, and as the cost of conventional drinking water treatment continues to increase, interest in the development of non-traditional water resources such as desalination and water reuse increases. Reverse osmosis (RO) is the predominant technology employed in inland brackish groundwater desalination in the United States, but the potential for membrane fouling and scaling generally limits the system recovery. The general hypothesis of this research is that electrodialysis (ED) technology can be employed to minimize the volume of concentrate waste from RO treatment of brackish water (BW) and thereby improve the environmental and economic feasibility of inland brackish water desalination. The objective of this research was to investigate the performance sensitivity and limitations of ED for treating BWRO concentrate waste through careful experimental and mathematical analysis of selected electrical, hydraulic, and chemical ED variables. Experimental evaluation was performed using a laboratory-scale batch-recycle ED system in which the effects of electrical, hydraulic, and chemical variations were observed. The ED stack voltage showed the greatest control over the rate of ionic separation, and the specific energy invested in the separation was approximately proportional to the applied voltage and equivalent concentration separated. An increase in the superficial velocity showed marginal improvements in the rate of separation by decreasing the thickness of the membrane diffusion boundary layers. A small decrease in the nominal recovery was observed because of water transport by osmosis and electroosmosis. Successive concentration of the concentrate by multiple ED stages demonstrated that the recovery of BWRO concentrate could significantly improve the overall recovery of inland BWRO systems. A mathematical model for the steady-state performance of an ED stack was developed to simulate the treatment of BWRO concentrates by accounting for variation of supersaturated multicomponent solution properties. A time-dependent model was developed that incorporated the steady-state ED model to simulate the batch-recycle experimentation. Comparison of the electrical losses revealed that the electrical resistance of the ion exchange membranes becomes more significant with increasing solution salinity. Also, a simple economic model demonstrated that ED could feasibly be employed, especially for zero-liquid discharge.

Download or read book Time variant Solar powered Electrodialysis Reversal Desalination for Affordable Off grid Clean Water Supply written by Anne-Claire Le Hénaff and published by . This book was released on 2019 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research is to design affordable photovoltaic-powered electrodialysis reversal systems capable of desalinating brackish water in remote locations of developing countries, and thereby increase the availability of freshwater in water-stressed areas such as rural India. At the village scale, electrodialysis technology for brackish groundwater desalination has the potential to substantially reduce water wastage and energy consumption compared to on-grid reverse osmosis (RO) plants currently commercialized. Moreover, PV-powered systems can supply water in off-grid locations where on-grid systems cannot be installed, at no environmental cost. However, the levelized cost of water achieved by state-of-the-art PV-EDR systems is still prohibitively high for cost-constrained communities, due to the large battery capacity required to reshape the solar power profile and accommodate the inflexible power profile of the desalination load in constant operation. To reduce water cost, a novel, flexible operational strategy for PV-EDR systems is presented and experimentally validated on a full-scale pilot. By actively controlling voltage and flow rate with a dedicated hardware and software architecture, the ED power consumption is matched to the available solar power at any time. The experimental fraction of solar energy directly used reached 76%, which is 91% higher than in the constant operation case, where the PV-EDR system runs at constant voltage and flow rate. As a result, the experimental system dynamically adapted its desalination rate to the solar irradiance profile, producing freshwater in synchronization with the sun while reducing the need for batteries by 92% on average compared to the conventional operation. Because desalination efficiency decreases as a function of operating power, it is suggested that a small battery capacity would allow reshaping the direct solar power profile into a more suitable profile for water production. If optimally managed, a 3 kWh battery addition on the experimental setup is predicted to increase water production by 25%. A machine-learning-based algorithm was designed to predict the optimal battery management strategy online and is demonstrated in simulation to achieve over 99% of the ideal water production. Shifting from constant to flexible operation is expected to reduce the levelized cost of water by 22% compared to current state-of-the-art PV-EDR systems. This number was obtained by optimizing the flexible PV-EDR system design to minimize levelized cost of water (LCOW) while answering daily demand for one year for a case study village location in Chelluru, India. Most importantly, the optimal flexible PV-EDR system is shown to be cost-competitive with current on-grid community-scale RO desalination solutions in India. Cost projections for ED membrane and brine disposal show that in the future, PV-EDR could produce water at 60% of the cost of water produced with on-grid RO.