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Copyright of Water Conservancy Science & Techonlogy & Economy is the property of Water Conservancy Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Social structure is based on the availability of the Water-Energy-Food Nexus. To cover these needs of society, several solutions of different scales of infrastructures coexist. The construction of infrastructure is capital-intensive; therefore, investment risk is always a consideration. In this paper, we try to evaluate the investment risk by interest rates (IR). We show that IR is a key indicator, which includes multiple parameters of prosperity expressing the political and economic status quo of the society. The selection of a particular scale influences the required capital and is thus one of the most critical decisions. Water supply infrastructure is one of the foundations of society, and the selection of the optimal scale of such infrastructure is often a great challenge in civil engineering. As a case study, we analyse three different scales of water supply infrastructures for the area of West Mani (Greece), i.e., dam, water ponds, and seawater desalination. We evaluate each case by the capital intensity by performing stochastic simulations of interest rates and identify the optimal solution as the one with the smallest median unit cost, in this case, the water ponds. In order to assess the impact of the development level of a country on the resulting unit cost stochastic properties we apply the optimal solution to various countries with different development levels and IR. We show that IR in the least developed countries, being generally higher and more variable, increases the unit cost, including its variability, which ultimately indicates higher investment risk. [ABSTRACT FROM AUTHOR]

Seawater membrane distillation (SWMD) is a promising separation technology due to its ability to operate as a stand-alone desalination unit operation. This paper reviews approaches to improve laboratory-to-pilot-scale MD performance, which comprise operational strategies, module design, and specifically tailored membranes. A detailed comparison of SWMD and sea water reverse osmosis is presented to further analyze the critical shortcomings of SWMD. The unique features of SWMD, namely the ability to operate with extremely high salt rejection and at extreme feed concentration, highlight the SWMD potential to be operated under zero liquid discharge (ZLD) conditions, which results in the production of high-purity water and simultaneous salt recovery, as well as the elimination of the brine disposal cost. However, technical challenges, such as thermal energy requirements, inefficient heat transfer and integration, low water recovery factors, and lack of studies on real-case valuable-salt recovery, are impeding the commercialization of ZLD SWMD. This review highlights the possibility of applying selected strategies to push forward ZLD SWMD commercialization. Suggestions are projected to include intermittent removal of valuable salts, in-depth study on the robustness of novel membranes, module and configuration, utilization of a low-cost heat exchanger, and capital cost reduction in a renewable-energy-integrated SWMD plant. [ABSTRACT FROM AUTHOR]

The use of renewable energy for desalination started in the 1980s, in order to provide a sustainable water supply in windy/sunny areas with water shortages. Nevertheless, this initiative has been generally limited to the R&D field and prototypes, with few units operating under real conditions. The research tradition in this field carried out by the Canary Islands Institute of Technology, based on pilot facilities, resulted in wide expertise on practical issues, as well as a deep knowledge on the state of the art. This paper deals with the most relevant technical aspects to be considered in the optimal design and operation of wind/photovoltaic (PV)-powered reverse-osmosis (RO) systems, focusing on practical indications: appropriate pre-treatment, the use and selection of the RO energy recovery system (ERD), the selection of an energy storage system, key recommendations for the O&M actions in wind- and PV-powered RO systems (extracted from the experience of operating different units in remote locations (PV and RO) and coastal areas (wind and RO)), and an identification of the pros and cons of hybrid systems. A selection of economic data is given, indicating the main aspects of the minimization of the cost of water. Finally, the paper mentions the latest advances in the involved technologies. [ABSTRACT FROM AUTHOR]

In this study, we present a novel methodology to design and optimally operate a standalone winddriven reverse osmosis desalination plant to provide the required water production in face of fluctuating wind power. The methodology is applied to a plant with a capacity of 2,592 m3/h for a rural area in Saudi Arabia. The plant nominal size, operating conditions, and the number of wind turbines are determined through numerical simulations. The performance of the desalination plant is tested under fluctuating wind power using two different operation strategies that allow for better leverage of the generated wind power. It is found that the desalination system can provide the annual production capacity if the feed pressure is optimally adapted in response to the varying wind speed. Another successful strategy involves the optimal use of the plant vessels in face of fluctuating wind power. Both strategies are successful but necessitate the use of a control system to automatically adapt the feed pressure or the plant active vessels during wind power variations. Moreover, the economic analysis signified a water cost as low as 0.45 $/m³ for the studied plant. [ABSTRACT FROM AUTHOR]

Copyright of Revista FAVE is the property of Universidad Nacional del Litoral and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An off-grid multi-generation model (solar photovoltaic, wind power, and diesel) has been used to assess the performance of a low scale (up to 250 m3/d) seawater reverse osmosis desalination plant with four different operating modes: fix, variable (180-250 m3/d), modular-fix (100 + 150 m3/d) and modular-variable operation (100 + 115-150 m3/d). The high-pressure pump and energy recovery system have been selected for each case according to the flow requirements; reverse osmosis membrane simulations have been made to know the power demand, product water flow and quality for the whole operating range of each option. The use of real solar and wind data allows to preliminarily assess the performance of the system. A specific battery charge/discharge strategy has been considered to take maximum advantage of wind and solar available energies. The most relevant technical and economic results have been presented, finding out the pros and cons of the different analyzed cases. A sensitivity analysis complements the study to identify the key parameter values addressed to achieve a minimum water cost under 2.2 €/m3. A new index is proposed to assess the performance of the whole system. [ABSTRACT FROM AUTHOR]

A technical and economic assessment has been made to simulate the operation of a wind energy-driven seawater reverse osmosis (SWRO) desalination plant (10,000 m³/d). Three different generation systems were compared: wind and batteries; wind and diesel; wind and photovoltaic (PV). In each case, two options of the SWRO plant were considered: variable operation high-pressure pump and modular plant consisting of three different trains operated independently. The ranges of power demand of said options are 81%-100% and 20%-100% of the nominal value, respectively. The energy lost, operation time, water production and water costs for each case were calculated, concluding design recommendations with the best technical and economic criteria. Water cost was identified in the range 1-1.35 €/m³, operation time under renewable energy supply can reach 75% of the year for modular reverse osmosis plant. A sensibility study for the water cost, for different parameters (capacity of batteries, diesel price, and PV power) was carried out for the different off-grid generation systems. [ABSTRACT FROM AUTHOR]

A technical and economic assessment of wind-powered seawater reverse osmosis (SWRO) systems is presented to identify the best combination of coupling between wind power and demanded power for a 5,000 m³/d SWRO unit. Three situations have been studied: Reference or Case 0) SWRO plant operating at the nominal point all of the time; Case 1) SWRO plant operating with variable power demand (up to 67% of the nominal point) by reducing the rotation speed of the high pressure pump, and Case 2) use of a modular SWRO plant, able to operate at four different values of power consumption by means of configuring two units of 1,250 m³/d and a unit of 2,500 m³/d. Power and fresh water production are calculated through a year based on experimental data of wind availability with time steps of 1 h. A comparative techno-economic analysis is performed to identify the best configurations along with recommendations on nominal values of desalination capacity and battery capacity in relation to the nominal power of the wind turbine installed. [ABSTRACT FROM AUTHOR]

In this paper, nanofiltration (NF) was investigated as a suitable technology for defluoridating brackish groundwater. A comparison between NF and reverse osmosis (RO) was performed to evaluate which method is the best for removing fluorine from groundwater to produce drinking water. Although NF employs a membrane that requires a low amount of energy, both NF and RO have advantages and limitations. NF and RO have similar costs for desalinating brackish water, and thus both the membranes can be used for this aim, but we believe that this will change with the next generation of NF membranes. [ABSTRACT FROM AUTHOR]

Information regarding domestic water consumption is vital, as the Kathmandu Valley will soon be implementing the Melamchi Water Supply Project; however, updated information on the current situation after the 2015 Gorkha Earthquake (GEQ) is still lacking. We investigated the dynamics of domestic water consumption pre- and post-GEQ. The piped water supply was short, and consumption varied widely across the Kathmandu Upatyaka Khanepani Limited (KUKL) branches and altitude. The reduction in piped, ground, and jar water consumption and the increase in tanker water consumption post-GEQ appeared to be due to the impact of the GEQ. However, the impact did not appear to be prominent on per capita water consumption, although it was reduced from 117 to 99 L post-GEQ. Piped, ground, and tanker water use were associated with an increase and jar water use was associated with a decrease in water consumption. Despite improvements in quantity, inequality in water consumption and inequity in affordability across wealth status was well established. This study suggests to KUKL the areas of priority where improvements to supply are required, and recommends an emphasis on resuming performance. Policy planners should consider the existing inequity in affordability, which is a major issue in the United Nations Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

This paper presents an overview of using solar energy in running desalination systems, called solar desalination. Solar energy can be converted directly to electric energy, which can operate electrically driven desalting systems such as reverse osmosis (RO), electrodialysis (ED), and mechanical vapor compression systems. Solar energy can also be converted to the thermal energy that can operate the mainly used thermally operated desalination system such as multistage flash (MSF), conventional multieffect (ME), and multieffect thermal vapor compression (ME-TVC), and emerging membrane distillation and humidification–dehumidification desalination systems. The thermal energy converted from solar energy can also be used to produce high-pressure steam running power plant producing electric power to operate mechanically driven desalting systems, and/or extracted steam at relatively low pressure to operate thermally driven desalting system. The main obstacle that hinders the use of solar desalination is the initial investment cost. This paper discusses the use of the solar desalination and calculates the investment cost to install solar desalination plants. These include photovoltaic (PV)-driven RO system, and thermally driven MSF and ME plants by steam directly generated by solar collectors, or by steam extracted from solar steam power plants operated by the concentrated solar collectors. The results revealed that PV-RO desalting system has the highest specific capital cost, among the considered systems, because the expensive storage of the electric energy in batteries, and the fact solar energy supply lasts about one third of the day. It showed also that using the thermally generated energy from concentrated solar collectors operating power plant is much cheaper than using this thermal energy when directly operating the desalination system. [ABSTRACT FROM PUBLISHER]

In this paper, research has been conducted on the floating type nuclear power plant named as ABV reactor which is designed for district heating, power, and sea water desalination by OKBM facility at Russia. This reactor was tested under different thermal loads during the designing phase, and three modules have been investigated. Theoretical calculations and simulation studies have been performed on these three modules having specifications as ABV-6M with 47MWth, ABV-6 with 38MWth, and ABV-3 with 18MWth.The results obtained from these modules have been calculated mathematically and verified by simulation. We have compared the originally derived data of ABV desalination system with our theoretical and simulation analysis. The results from two desalination techniques including RO and RO + MED have been calculated and are presented in this paper with details. The results obtained from both analysis show that the efficiency of ABV nuclear reactor desalination system increases with the decrease in corresponding water cost ratio. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Reverse osmosis (RO) has contributed to a large extent in positioning membrane desalination as one of the best available technologies to meet water demand in dry coastal areas. However, membrane desalination may still be perceived as an energy consuming and high cost desalination technology. Seawater Osmotic Dilution (SOD) may lower the energy consumption and the water cost by decreasing the salt content of seawater; and, at the same time SOD can become a sustainable technology that does not impact marine environments considering that less concentrated brines are discharged into the sea. The main objective of this study was the economical evaluation of SOD for the purpose of decreasing desalination costs. The authors have investigated the attractiveness and viability of SOD opportunities compared with standard RO membrane desalination. Three process configurations (desalination, desalination and reuse, SOD) were defined for a coastal area location, where the possibilities of water availability are limited to mainly the ocean. For each configuration, three different water production capacities (1.000, 10.000, and 25.000 m³/day) were studied and evaluated economically in terms of capital expenditure (CAPEX) and operational expenditure (OPEX). The results show that SOD can produce desalinated water with 27% energy reduction compared with seawater reverse osmosis desalination; and that operational costs of desalination can be reduced by 31%. Water volume balances of each configuration demonstrate that SOD has a high potential in dry coastal areas with limited availability of fresh water. For SOD with a commercial price of forward osmosis (FO) membranes at 30–60 US$/m² and a membrane flux of 7–14 L/m²-h, SOD becomes a viable technology for lowering costs of desalination, with payback times of less than 1.5 years when compared with desalination. [ABSTRACT FROM PUBLISHER]

The main two supply of potable water to Amman city are Zai water treatment plant (represent 60%) and Wadi Ma'in, Zara, and Mujib (WMZM) water treatment plant (represent 30%). WMZM receives raw water from three main sources originally flowing to the Dead Sea, now collected and conveyed to a raw water reservoir at the treatment plant to produce about 110,000m3/day. WMZM was commissioned in 2006 and still operating at the original design capacity. WMZM water treatment plant and its conveyance system are presently operated by Jordan Water Company-Miyahuna. This paper covers the plant description, original design parameters, and RO membrane performance after more than five years of operation. [ABSTRACT FROM AUTHOR]

The paper presents part of the work that has been elaborated within the project entitled "Promotion of Renewable Energy Sources (RES) through Desalination", PRODES, IEE/07/781/ SI2.499059, Intelligent Energy EU Programme. Part of the project work is dedicated to the analysis of the energy and water framework in four target countries, that is, Greece, Italy, Portugal and Spain. The present paper is focused on the current situation of the energy and water in Greece as well as on the legislation and administrative framework for RES and Water Desalination. Energy tariffs and water costs from conventional or alternative resources are also presented. The output of this work includes recommendations for policy makers, suggestions on the improvement and acceleration of the procedures, and further progress of RE-Desalination in Greece. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the exergy cost of water supply as well as technologies involved in water treatment. It obtained an index like the unit exergy cost (UEC) of different water-related technologies which is based on exergy analysis (EA). It mentioned that aside from their embedded energy-efficiency information, UEC values can used in the assessment of water costs.

This paper addresses the effect of the oil prices on the cost of low pressure heating steam for thermal desalination systems, electricity and desalinated water. Two methods of calculating the low pressure steam, and electricity are developed and compared with a typical power/ water cogeneration plant commissioned in 2009, by the King of Saudi Arabia. The first method is based on the calculation of the monetary cost of all streams of power cycle and charging the levelized capital and operating and maintenance costs based on exergy. The cost of bleeding steam is allocated based on the steam quality. In the second method we calculate the low pres- sure steam of the back pressure turbine based on equivalent cost of power loss due to the steam withdrawal for desalination plant. Visual Design and Simulation Program (VDSP) previously developed by the authors is used. The effect of a wide range of the oil price (5-100 $/bbl) is investigated. The results showed that the second method overestimates the electricity cost by 8% and underestimates the low pressure steam cost by 25% at oil price of 70 $/bbl. The results showed also that, the product water, electricity, and steam costs are significantly affected by the variation in oil price. The product water cost will be less than 1.0 $/m³ only if oil price is subsidized to near to 20 $/bbl. However, the water unit cost may jump to 4 $/m³ when the oil price increased to 100 $/bbl. [ABSTRACT FROM AUTHOR]

A new approach for evaluating water sustainability is introduced by comparing physical and economic sustainability. To achieve physical sustainability, water should be available in sufficient quantity and of good quality and used efficiently. The economic sustainability can be achieved by balancing between costs and values of water. The objectives of this study were to estimate the physical and economic sustainability of surface water in the Big Lost River, south–central Idaho. The study used a Bayesian network by building a graphical diagram of nodes representing all significant variables related with the sustainability, such as water demand, water quality, and the different costs and values of water. The study showed that the likelihood of the physical sustainability is less than that of the economic sustainability, which is attributed to the scarcity of water in the Big Lost River. [ABSTRACT FROM AUTHOR]

Many regions of the world are facing formidable freshwater scarcity. Although there is substantial scope for economizing on the consumption of water without affecting its service level, the main response to water scarcity has been to increase the supply. To a large extent, this is done by transporting water from places where it is abundant to places where it is scarce. At a smaller scale and without a lot of public and political attention, people have started to tap into the sheer limitless resource of desalinated water. This study looks at the development of desalination and its costs over time. The unit costs of desalinated water for five main processes are evaluated, followed by regressions to analyze the main influencing factors to the costs. The unit costs for all processes have fallen considerably over the years. This study suggests that a cost of $1/m3 for seawater desalination and $0.6/m3 for brackish water would be feasible today. The costs will continue to decline in the future as technology progresses. In addition, a literature review on the costs of water transport is conducted in order to estimate the total cost of desalination and the transport of desalinated water to selected water stress cities. Transport costs range from a few cents per cubic meter to over a dollar. A 100 m vertical lift is about as costly as a 100 km horizontal transport ($0.05-0.06/m3). Transport makes desalinated water prohibitively expensive in highlands and continental interiors but not elsewhere. [ABSTRACT FROM AUTHOR]

Water consumption continues to grow globally, and it is estimated that more than 160% of the total global water volume will be needed to satisfy the water requirements in ten years. In this context, non-conventional water resources are being considered to overcome water scarcity and reduce water conflicts between regions and sectors. A bibliometric analysis and literature review of 81 papers published between 2000 and 2020 focused on south-east Spain were conducted. The aim was to examine and re-think the benefits and concerns, and the inter-connections, of using reclaimed and desalinated water for agricultural and urban-tourist uses to address water scarcity and climate change impacts. Results highlight that: (1) water use, cost, quality, management, and perception are the main topics debated by both reclaimed and desalinated water users; (2) water governance schemes could be improved by including local stakeholders and water users in decision-making; and (3) rainwater is not recognized as a complementary option to increase water supply in semi-arid regions. Furthermore, the strengths–weaknesses–opportunities–threats (SWOT) analysis identifies complementary concerns such as acceptability and investment in reclaimed water, regulation (cost recovery principle), and environmental impacts of desalinated water. [ABSTRACT FROM AUTHOR]

This paper analyzes the importance of the cost of dam water use in hydroelectric generators according to the International Financial Reporting Standard (IFRS) and Management Accounting. Not valuing the use of water from dams would imply undervaluing energy generation service, leading to a lack of reasonability in the Financial Statements of electricity generators. For this reason, it is vital to recognize that dam water has a cost that directly impacts the Statement of Financial Position as an asset and later, in energy generation and commercialization, its cost will impact the statement of profit or loss, according to the IFRS as good accounting and financial practices around the world. Said cost will also be an important indicator for rationalizing consumption, defining public policy, or determining energy tariffs. An empirical study is conducted for Colombia and Norway, two of the main countries in the world whose primary source of energy generation is water. The results evidence the need for hydroelectric generators to present the cost of their hydric reserve as intangibles inventories because of its potential capacity to generate electric power. Additionally, there is a positive and significant relationship between the cost of water and the price of energy, and a negative relationship between the price of energy and dam levels. [ABSTRACT FROM AUTHOR]

Future agricultural development will be challenged by the impacts of climate change on water, which are expected to be particularly strong in southern European regions. Thus, exploring interrelations between agriculture and water under climate change is essential to frame informed policies that ensure sustainable water management while enhancing food production. Nevertheless, studies that address future agriculture development focus on climate-induced changes in crop productivity and often disregard the water dimension. In this research, we have conducted a sensitivity analysis of agricultural development to drivers of water use in Andalusia in 2050 based on outcomes from the CAPRI-Water model. The results from the analysis show that water cost is the most determinant factor in shaping agricultural land, offsetting the impact of the driver of water availability. In contrast, irrigation water use is driven not only by water cost but also by irrigation efficiency. The magnitude of the sensitivity to these drivers differs significantly across crops. Policies aimed at improving resource use efficiency can contribute to strengthening the resilience and adaptation capacity of future agricultural systems to climate change. To achieve this goal, the policies must consider crop sensitivity to irrigation costs and the potential rebound effect. [ABSTRACT FROM AUTHOR]

This paper presents a detailed estimation of the fabrication cost, water production cost (WC), and cost payback period (CPP) using annualized life cycle costing for a tubular solar still (TSS). The operation and maintenance cost (OM) and the number of sunny days in a year (d) have a significant effect on the WC. The WC is raised from 3.1 to 4.4¥/L, if the OM increases from 5 to 18% of the capital cost, respectively. The WC is dropped by 35% (in average) when the d increases from 230 to 350 days. In addition, the CPP is greatly affected by the water selling prices and d. The CPP is dropped from 68 to 45 days due to the increase of d from 230 to 350 days (in average), respectively. The fabrication cost of the TSS ($5) and the WC ($31/m³) are affordable and much lower than the single-sloped passive solar still. Finally, it is revealed that the solar radiation is the most influential parameter on the productivity of TSS and a linear proportional relationship is found between them. [ABSTRACT FROM AUTHOR]

In this paper, a solar desalination system with evacuated tube collectors (ETCs) and low-temperature multi-effect distillation (LT-MED) is developed. It solves the problem of shortage of fresh water, while it also avoids the consumption of non-renewable energy resource and environmental pollution. The system configurations designed consist of ETCs, heat storage tank, flash tank, multi-effect distillation, electrical heating and cooling, and so on. Mathematical and economic models are established based on mass and energy conservation, and the thermal and the economic performance of the solar desalination system is analyzed by utilizing MATLAB. In this paper, the fresh water cost reduces with both the increasing of the area of ETCs and collector outlet water temperature. Recommendations given in this paper could be helpful in future initiatives regarding the research and development of this promising solar desalination technology. [ABSTRACT FROM AUTHOR]