Energy and cost allocation in dual-purpose power and desalination plants

Renewables desalination plant gets all clear

The role of desalination in bridging the water gap in Jordan

Hybrid systems in seawater desalination-practical design aspects, status and development perspectives

Madura Island, which comprises 5.3 thousand square kilometres and is inhabited by 3.1 million people, belongs to the East Java Province of Indonesia. Proximity to the congested Surabaya city-port makes Madura enticing as a place to accommodate the expansion of port facilities and industrial estates operating in Surabaya. Efforts to support industrial development have been made, e.g. in the construction plan for a 6 km connecting bridge as well as in respect of power and water reliance. Power demand has been predicted to reach 119 to 136 MW by 2007 and 221 to 292 MW by 2015. Since electricity to the island is connected to the Jawa-Bali grid, system expansion can be solved within the Jawa-Bali expansion-planning scheme. In 1998, however, the breakage of the submarine power cables resulted in a blackout of the whole island for forty days, which encouraged planners to launch the idea of a self-reliance scenario within the island. Fossil power plants (100 to 200 MW) are sought to become candidate solutions for 2007, whereas a nuclear alternative comes into consideration for 2015. Their are four water municipalities (Regencies), which in total produce clean water equivalent to 120 L/capita/day for only 5.8% of the inhabitants with a distribution loss of 18-35%. It is obvious that water demand is suppressed and that the quantity required, on which to base planned expansion, depends upon the amount of industrial development. The present water capacity required to meet the four Regencies' demands ranges from 18,000-23,000 m³/day. However, since water supply solutions are limited to each locality (and not integrated for the whole of Madura), the expansion plan can only start by aiming for a modest capacity increase, which is sought to be around 4,000 m³/day in 2007 growing over the years with unit additions. Should a power and desalination plant be built, the rejected brine would become a useful input to salt production, enabling traditional methods (used on the island for a long time) to lower costs by 19% and create 36% more efficient land-use. A preliminary economic assessment to this date denotes a gas-fuelled combined cycle plant to be the best candidate to power the project, thanks to the availability of gas basins offshore near to Madura Island. This nuclear alternative is sought to come into competition with the fossil ones in 2015, being the nearest possible introduction to the island deployment. Additional requirements, however, to the design of the nuclear plant and its safety features to accommodate the local environment are crucial. Tripartite cooperation with the KAERI and the IAEA is proceeding to provide assistance with the study of technologies and expertise for the project.

طی دوره‌ی 2010 تا 2016 بازار نمک‌زدایی آب با رشد سالانه‌ی 9 درصد و مجموع سرمایه‌گذاری 88 میلیارد دلار، یکی از پررونق‌ترین بازارهای جهان بوده است. رشد شتابان بیش از 60 درصد ظرفیت جهانی نمک‌زدایی، نه تنها حکایت از سهیم شدن دریاها در تأمین آب شرب کانون‌های جمعیتی سواحل دارد، بلکه گویای زوال تدریجی کیفیت آب‌های داخلی نیز می‌باشد. پیش‌بینی افزایش دما و تقلیل بارندگی در افق 2050 در بیست کشور واقع در شمال آفریقا و غرب آسیا (منطقه‌ی منا) منابع جدید آب را در این منطقه‌ی حساس جهان، کمیاب‌تر و دسترسی به آن‌ها را پرهزینه‌تر کرده و دولت‌ها را به ناچار به سمت گزینه نمک‌زدایی آب پیش می‌برد. در مقیاس جهانی، 38 درصد از حجم روزانه‌ی تولید جهانی آب نمک‌زدایی شده (2/65 میلیون متر مکعب) متعلق به کشورهای منطقه‌ی منا است و در محدوده‌ی جنوبی خلیج فارس، ظرفیت نصب شده نمک‌زدایی آب از 10 میلیون متر مکعب در روز فراتر است. پایه و اساس فرآیندهای گوناگون نمک‌زدایی آب، بر بهره‌گیری از انرژی استوار است و هر گونه تحلیل، سیاستگزاری و آینده‌نگری در موضوع نمک‌زدایی آب، بدون لحاظ سیاست‌های انرژی، ناقص خواهد بود. مهم‌ترین مسئله‌ی زیست محیطی این تأسیسات، شورابه‌های آن‌ها است که در گروه پساب‌های صنعتی قرار داشته و تخلیه‌ی گسترده‌ی آن‌ها به خلیج‌ها و سواحل مرجانی، سبب تغییر گونه‌ها و تهدید حیات آبزیان می‌شود. در سال‌های اخیر با توسعه و بهینه‌سازی فرآیندها، هزینه‌ی نمک‌زدایی هر متر مکعب آب، به حدود نیم دلار تقلیل یافته است، اما قیمت بازار آن هم‌ چنان در محدوده‌ی یک تا دو دلار باقی مانده است. ظرفیت نمک‌زدایی آب در ایران افزون بر 450 هزار متر مکعب در روز است که 65 درصد آن مربوط به آب شرب است. این مقدار کم‌تر از 2 درصد ظرفیت جهانی نمک‌زدایی آب است.

Seawater desalination: Study of three coastal stations in Algiers region

Triangle of Environment, Water and Energy: A Sociological Appraisal

Heterogeneous network, which is a key technology of fifth generation(5G) mobile communication system, can effectively solve the spectrum resource shortage in the communication system. However, with densified deployment of base stations (BSs) and growth of user quantity and communication data size, the system energy consumption of BSs has imposed enormous economic pressure on network operators. As a result, energy consumption decreases and cost of communication system becomes a problem that requires urgent solutions. Renewable energy power generation devices of BSs have provided an opportunity for solving this problem with the development of smart power grids. However, the production rate of renewable energy sources presents intense volatility because of the influence of weather factors. This condition brings new challenges to the energy allocation of communication system. Therefore, an energy sharing link between BSs was established in a heterogeneous wireless network, and the distance between macro-BS and micro-BS was taken as an index. The energy consumption-based energy and user joint allocation method and energy cost-based energy and user joint allocation method were proposed. The two multi-objective optimization problems were converted into two convex optimization problems, and the optimal allocation strategies were solved using convex optimization toolbox. Simulation results indicate that the energy consumption-based allocation method takes energy consumption as the optimization objective and makes the shared link transmit energy sources as few as possible. This way reduces energy consumptions of the link and the system. Starting from the economic angle, the energy cost-based allocation method considers the influence of energy price, coordinates energy allocation between BSs based on energy cost using the shared link, and optimizes energy allocation among BSs at each time slot. Therefore, the method can reduce the energy cost of the system by a large margin.

An integral and multidimensional review on multi-layer perceptron as an emerging tool in the field of water treatment and desalination processes

Desalination of brackish water by nanofiltration and reverse osmosis

Stress mitigation of conventional water resources in water-scarce areas through the use of renewable energy powered desalination plants: An application to the Canary Islands

The intensive development of the world economy and the expected population growth mean that demand for cooling and water will continue to rise. The use of conventional technologies to meet this demand is associated with an enormous expenditure of electricity, which still comes mainly from non-renewable sources. With the increasing demand for energy, the increasing scarcity of drinking water, and the negative impact of humankind on the environment due to global warming and ozone depletion, intensive research has been carried out to find modern desalination technologies Most of the technologies use electricity for the process of desalination, and over 6% of the world’s electricity is generated from non-renewable sources, thus increasing the emissions of harmful pollutants into the atmosphere. One possibility to reduce emissions is the use of adsorption chillers with desalination function, which allow the production of cooling simultaneously with the process of water desalination. These systems can be powered by low-temperature waste heat from industrial processes or from renewable sources (solar panels) and require little electricity to operate. This paper presents options to improve their performance and increase the production of condensate in the process of desalination of saline water. Moreover, also presented are the results of tests carried out on a two-bed adsorption chiller with desalination function. The aim of the study was to determine the effect of cycle time on the cooling coefficient of performance (COP) and on the production of condensate from water desalination. The obtained results confirmed that increasing the adsorption and desorption cycle time leads to an increase in the COP value of the adsorption chiller, but the efficiency of the desalination process and condensate production decreases with increasing cycle time.

Although current water desalination technologies are mature enough and advanced, the shortage of freshwater is still considered as one of the most pressing global issues. Therefore, there is a strong incentive to explore and investigate new potential methods with low energy consumption. It is well-known that polymer hydrogel network has the ability to absorb water via swelling. In the case of polyelectrolyte hydrogels, the charges localized on the polymer chains, which mainly drive the swelling pressure inside the hydrogel, can also separate added salt via charge-based selectivity (Donnan exclusion). When combining this material with a temperature-sensitive polymer, the heat generated by solar energy can trigger the desorption process via conformational change of polymer chains. Hence, hydrogels designed from both materials, polyelectrolyte and thermo-responsive polymer can reduce the salinity of water, such as brackish water by means of reversible thermally-induced absorption and desorption desalination processes. In addition, the desorption process can also be achieved based solely on a polyelectrolyte hydrogel system by altering the ionization of charges within the hydrogel via pH. In this thesis, hydrogel-based water desalination process were developed using acrylic acid (AAc)/sodium acrylate (SA)-based polyelectrolytes as the charge-based separation function, alone or with a combination of N-isopropylacrylamide (NIPAAm) as thermo-responsive comonomer. In the latter case, a series of chemically cross-linked polymeric hydrogels were synthesized via either free radical-initiated copolymerization or reversible addition-fragmentation chain transfer (RAFT) polymerization, thus realizing different macromolecular architecture. According to the nature of hydrogels, the reversible sorption/desorption state were triggered by either chemical stimulus (pH), or physical stimulus (heat) as the thermo-responsive polymer introduced into the hydrogels. In detail, the effect of hydrogel composition as well as the influence of the macromolecular architecture on the swelling/deswelling behavior for the synthesized hydrogels were studied. For this, their properties including their responses to external stimuli were investigated, and their ability to desalinate brackish water as well as the effciency of such desalination process were evaluated. Generally, the results demonstrated correlations between macromolecular architecture of the network structure and their performance in the proposed desalination process, such as salt rejection and desalination capacity. Moreover, the potential of the best performance materials for applications was also discussed.

During the past few decades, rapid progress in reducing the cost of photovoltaic (PV) energy has been achieved. At the megawatt (MW) to gigawatt (GW) scale, large PV systems are connected to the electricity grid to provide power during the daytime. Many PVs can be installed on sites with optimal solar radiation and other logistical considerations. However, the electricity produced by the PV power plant has to be transmitted and distributed by the grid, which leads to more power losses. With the widespread commissioning of the large-scale solar PV power plants connected to the grid, it is crucial to have an optimal energy allocation between the conventional and the PV power plants. The electricity cost represents the most significant part of the budget in the power distribution companies, which can reach in many countries billions of dollars. This optimal energy allocation is used to minimize the electricity cost from buyers’ (distribution companies) point of view rather than sellers’ (owners of power plants, i.e., investors) point of view. However, some constraints have to be considered and met, such as water demand, network limitations, and contractual issues such as minimum-take energy. This paper develops a model for the economic energy allocation of conventional and large-scale PV power plants, which considers both the operational aspects and the contractual provisions. The model can be used either in the design or operation phases to minimize the operating cost. Moreover, the proposed model can be used for budgeting tasks. The developed model is entirely generic and can be used for any country or electricity system regardless of the PV energy contribution. Furthermore, the Al-Karsaah power plant located in Qatar is discussed as a case study to validate the claimed contribution.

Potential of nuclear desalination in the Arabian Gulf countries