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Qatar Foundation Annual Research Conference Proceedings Volume 2018 Issue 1
- Conference date: 19-20 Mar 2018
- Location: Qatar National Convention Center (QNCC), Doha, Qatar
- Volume number: 2018
- Published: 12 March 2018
101 - 142 of 142 results
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Screening of Qatari Microalgae and Cyanobacteria for Application in CO2 Utilization
CO2 fixation by phototrophic microalgae and cyanobacteria is seen as a possible global carbon emissions reducer, which could also be applied to produce useful products. In Qatar, the prospect of using microalgae is very promising: high solar irradiance, large areas of non-arable land, and large amounts of CO2 sources make it an ideal place for algae cultivation. Nonetheless, application of algae in the region is limited, primarily due to a lack of suitable algae which can grow under relevant outdoor conditions, such as high temperatures, increased salinities, as well as elevated CO2 concentrations when using industrial CO2 sources. Furthermore, such algae also need to be able to produce commercially valuable products. One of the most comprehensive resources for novel algae strains in the region is the Qatar University Culture Collection of Cyanobacteria and Microalgae (QUCCCM), which houses a large diversity of strains, the potential of which still remains largely unexplored. This research focused on evaluation of biomass productivity of four novel marine strains from this culture collection, under elevated temperatures and CO2 concentrations. The strains were also evaluated for their carbon capture potential, as well as commercial potential, through biomass analysis. Two strains were identified as cyanobacteria (Leptolyngbya sp. and Pleurocapsa sp.) and two were identified as microalgae (Tetraselmis sp. and Picochlorum maculatum). As cyanobacterial strains in some cases are known to produce toxins, both cyanobacteria were analyzed for presence of genes for cylindrospermopsin, microcystin and saxitoxin production, and found to be negative for all three. All four strains were then cultivated under various temperatures, ranging from 30 to 45˚C. The most productive strain was Tetraselmis sp., with a maximum biomass productivity of 157.7 ± 10.9 mg L-1 d-1 at 30˚C, with a decreasing productivity for increasing temperatures. Leptolygnbya sp. showed an opposite trend, increasing in productivity from 91.4 ± 10.2 to 106.6 ± 7.1 mg L-1 d-1 with increasing temperature from 30 to 40˚C respectively. None of the strains were able to grow at 45 ˚C. The biomass of the four strains cultivated under different temperatures was analyzed for lipid, protein and carbohydrate content, as well as total carbon and nitrogen content. Picochlorum maculatum was found to have the highest lipid and protein content, with 24.0 ± 1.3, 28.0 ± 1.4 and 27.0 ± 1.4 % (w/w) lipids and 21.2 ± 0.2, 23 ± 0.1, and 20 ± 0.9 % (w/w) proteins for cultivation at 30, 35 and 40˚C respectively. This strain also had the highest nitrogen content (12.2 ± 0.05 % at 40˚C) and carbon content (51.2 ± 0.25 % at 45˚C). Compared to Picochlorum maculatum, Tetraselmis sp. showed a slightly lower lipid content (25.6 ± 0.64 and 22.5 ± 0.78% for 30 and 35˚C respectively) and total carbon content (46.9 ± 0.8 and 47.6 ± 0.9% C (w/w) for 30 and 35˚C respectively), however due to the higher productivity, the carbon capture rate for Tetraselmis sp. was the highest of the tested strains, at 270 mg CO2 L-1 d-1 at 30˚C. Pleurocapsa sp. showed the lowest nitrogen content, at 4.4% N (w/w) for 30˚C. There is indication that this strain is capable of fixating atmospheric nitrogen. This is very beneficial for large-scale cultivation, as it reduces the requirements for nitrogen fertilizer, which can greatly reduce costs and improve production sustainability. Furthermore, spectrophotometric analysis of Pleurocapsa sp. and Leptolyngbya sp. showed production of phycobilin proteins, which can have a high commercial value. The tolerance of the strains to increased concentrations of CO2 in the gas phase was also studied for CO2 concentrations ranging from 5% to 30% (v/v). With productivities of 53.7 ± 11.4, 162.2 ± 5.4, 333.8 ± 29.1 and 312.8 ± 12.8 mg L-1 d-1 for 5, 10, 20 and 30% CO2 respectively, Tetraselmis sp. showed that a significant productivity increase could be obtained with increased CO2 concentrations. Picochlorum maculatum showed a similar trend, with slightly lower productivities of 67.1 ± 0.2, 160.5 ± 21.8, 244.1 ± 20.9 and 219.9 ± 15.6 mg L-1 d-1 for 5, 10, 20 and 30% CO2 respectively. Leptolyngbya sp. showed similar productivities for CO2 concentrations ranging from 5-30%, indicating that the strain was not influenced by increasing CO2 concentrations as were the other two strains. Pleurocapsa sp. on the other hand showed no growth at 30% CO2, and stable similar productivities at 5, 10 and 20% CO2. Overall, it can be concluded that for both microalgal strains (Tetraselmis sp. and Picochlorum maculatum) increased CO2 concentrations resulted in a significantly increased productivity, and as of such they would be the most interesting to further investigate for direct coupling to enriched CO2 gas sources, such as industrial flue gasses. Furthermore, besides having the highest productivities of the four investigated strains, Tetraselmis sp. is generally known to have promising characteristics for feed purposes (amino acid profiles and presence of omega-3 fatty acids) as well as for biofuel purposes due to high lipid amounts. Based on these results, Tetraselmis sp. is a very interesting candidate for CO2 capture and production of valuable products in Qatar. Further investigation into this strain is necessary to confirm the presence of such components in this particular strain, as well as to identify conditions which increase specific product productivity, and the capability of direct coupling to industrial flue gas.
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The state of the art prototype design and optimized process conditions for clathrate hydrate based desalination HyDesal process
Authors: Praveen Linga, Ponnivalavan Babu and Abhishek NambiarDesalination is one of the most promising technologies to mitigate an emerging water crisis. Thermal desalination and reverse osmosis are two of the most widely employed desalination technologies in the world. However, these technologies are energy intensive. In countries like Singapore which lack natural water and energy resources, it is imperative to develop innovative energy efficient technologies to strengthen the energy – water nexus. Clathrate hydrate based desalination (HyDesal) is one such technology. Clathrate hydrate based desalination (HyDesal) process is based on a liquid to solid phase change by employing a suitable guest gas/ gas mixture for the phase change. In the HyDesal process, water molecules form cages around a guest gas/liquid component effectively rejecting salts present in the brine solution at temperatures slightly higher than normal freezing temperature of water. These crystals when dissociated or melted are essentially fresh water and the guest component can be re-used for the process again. While HyDesal process was proposed almost 70 years ago, it was never commercialized primarily due to the high energy requirement for low temperature operation, slow hydrate formation kinetics and inefficient hydrate crystal separation from brine. Recently, we reported an enhanced hydrate formation kinetics in fixed bed reactor with silica sand as porous media when hydrate is formed from gas mixture consisting propane as co-guest. Based on the ability of propane to draw dispersed water from sand bed towards the gas phase for hydrate growth, we proposed a conceptual hydrate based desalination (ColdEn-HyDesal) process employing fixed bed reactor configuration to minimize the energy requirement. The ability of propane as a co-guest to draw water from the silica sand bed can be effectively used for the HyDesal process to address the slow kinetics and effective separation of the hydrate crystals. In this presentation, our state of the art prototype design and optimized process conditions will be presented. With our innovative reactor design, we carried out water recovery experiments to find the suitable guest gas mixture containing propane as co-guest. The other constituent in the gas mixture employed were methane, argon, nitrogen and carbon dioxide. Further kinetic experiments were carried out to optimize the silica sand particle size, bed height. Our recent knowledge on enhancing the kinetics of hydrate formation and innovative approach to offset the refrigeration cost for the HyDesal process can be applied to efficiently desalinate seawater to produce potable water. With our innovative reactor design and utilizing waste LNG cold energy, HyDesal can be a sustainable solution for desalination. The ColeEn-HyDesal process utilizing waste LNG cold energy will have a huge impact globally as well due to the expanding number of LNG terminals and the potential to mitigate the potable water issues.
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Effect of NaCl on clathrate hydrate based desalination HyDesal process with fixed bed approach
Authors: Praveen Linga, Ponnivalavan Babu and Abhishek NambiarAcute shortage of water has become one of the biggest problem facing many countries in the world. Safe and drinkable water is a basic necessity for survival. Hence, water resource management has become need of the hour. Since, seawater is the most abundant source of water available on the earth, desalination is one of the most promising technology to produce potable water. Desalination is the process of removal of salts and other impurities from seawater and brackish water. Thermal distillation and Reverse Osmosis (RO) are two of the most widely employed desalination technologies in the World. Thermal desalination uses energy inefficiently and also suffers from corrosion problems. RO on the other hand is used in more than 50% of the desalination plants in the World. In a typical RO desalination plant, water recovery from seawater is less than 55%. However, RO suffers from fouling problems which increase maintenance cost. Since, these technologies are energy intensive there is a need to address water-energy nexus by employing innovative energy efficient solutions. Clathrate hydrate based process which is based on freeze desalination approach has been proposed as a potential desalination technology to alleviate shortage of potable water in many parts of the World. Clathrate hydrate are non-stoichiometric crystalline solid compounds made up of water and gas. Similar to freeze desalination, clathrate hydrate excludes salts and other impurities present in seawater and brackish water from crystals. After separating formed hydrate crystals from left over brine, there is potential to get pure water and gas by decomposing hydrate crystals. Gas released during decomposition of hydrate can be recycled. In general, salts present in seawater act as thermodynamic inhibitor for gas hydrate formation. One of the major challenges faced by freeze desalination is ice crystal contamination due to crystal contact with left over brine. Similarly, hydrate contamination by left-over brine has prevented successful commercialization of HyDesal technology. Hence, efficient separation of hydrate crystals from brine and faster kinetics of hydrate formation play a major role in clathrate hydrate based desalination process. In order to strengthen energy-water nexus, waste cold energy from Liquefied Natural Gas (LNG) regasification terminals is being incorporated to mitigate energy requirement of this process. Previously, it has been reported that propane has shown ability to draw water out of fixed bed to form hydrates away from unreacted brine solution. Hence, there is a need to identify suitable co-guest gas with propane to maximize water recovery from HyDesal process. In the present work, an innovative approach has been employed by using Propane/ Nitrogen gas mixture in fixed bed made up of silica sand. Fixed bed approach in presence of propane enables natural separation of hydrate from left over brine which has been reported in an earlier work, which helps in minimizing hydrate contamination by salts present in left over brine. Faster kinetics has also been reported in fixed bed approach. In this work, water recovery from 1.5 wt% NaCl solution and 3 wt% NaCl solution has been studied and comparison has been made with kinetics of hydrate formation in deionized pure water. In this study, salt was found to act as kinetic inhibitor for hydrate formation.
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The Role of Tariffs in Reducing Residential Water Demand in Qatar
Authors: Hamish R Mackey, Huda Alkandari and Gordon MckayQatar is a hyper-arid country located in the Middle East suffering extreme water scarcity. More than 99% of municipal demand comes from seawater desalination while existing groundwater reserves are under severe pressure from over-abstraction. Despite these water resource limitations, per capita water demand is amongst the highest globally with recent Ministry of Development Planning and Statistics values placing per capita consumption at roughly 550 L/p.d in 2014. Such high demand could be due to a variety of cultural, social and political factors. The Qatar population is unique in its composition, with roughly 85% of the population being non-citizen residents coming from a diverse set of cultures including a large portion of low-skilled labourers. Therefore, promoting conservation in a consistent and effective manner can be challenging. The high average personal wealth in the country may also lead to greater luxury use of water. Cultural and environmental issues may also play a key role. For instance, the majority of the population are adherents of Islam, which has strict ablution requirements for purification prior to prayer and holds a high regard on cleanliness, which in the extreme weather conditions of the Arabian Gulf leads to increased water use for washing. However, the traditional welfare orientated governance of the Gulf States is frequently regarded as a primary cause for high water consumption prevalent in the region. Qatari citizens are granted tariff free use of domestic water on one dwelling while historically residents have been offered a heavily subsidized flat rate of only 4.40 QAR/m3 ($1.21 USD/m3). In 2015, the countries sole water utility provider, the General Electricity and Water Company (Kahramaa), revised the tariffs to various user groups including residents who now pay a tiered structure which still starts at 4.40 QAR m/3, but rises to 5.40 QAR/m3 after the first 20 m3 and has a final tier rate of 9.40 m3 reflecting a cost close to the true cost for supply. This study evaluated the effectiveness of this tariff restructuring by assessing changes in water consumption before and after the tariff changes across 547 residential properties including citizens and residents; flats and villas, and rented vs owned. Metering data was provided directly by Kahramaa following screening to ensure the same tenant was registered for two full years, one year prior and one year following the price restructuring. Data was analysed using SPSS statistical software (IBM), using non-parametric methods due to non-normality of the data. It was found that a statistically significant reduction in water consumption occurred following the tariff restructuring with a total reduction of 17% observed. Surprisingly, the most significant reductions were observed among Qatari rented flats, with resident rented flats and villas the next most responsive to tariff changes. The responsiveness of users was also assessed based on their previous water consumption by considering three groups, low water users (set as the 10th percentile users), medium water users (set as the median water users) and high water users (set as the 90th percentile users). While response varied significantly among household tenant types, overall it was found low water users responded significantly more to the changes in tariffs. This study highlights the importance of tariff use in Qatar as one effective tool to complement a broad and holistic approach to bring domestic water consumption to more sustainable levels and highlights the role tariff changes have on even those exempt from tariffs, possibly through increased discussion, awareness and feeling of responsibility.
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Selective Catalytic Valorisation of Carbon Dioxide Towards Building Block Molecules
The development of sustainable technologies for successful exploitation of C-1 feedstock such as carbon dioxide (CO2) is a thought-provoking challenge for effective utilisation of this abundant renewable resource. In an industrial prospective, new catalytic concept are vital to add value stream and to bring sustainability to this resource to mitigate the challenges associated with growing energy demands and increased responsiveness for climate control. Notably, catalysis is a key technology for achieving sustainable processes and the future development of humankind. Our recent efforts in developing catalytic methodologies towards selective valorisation of CO2 towards building block molecules will be discussed.
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Efficient Inhibition of SulfateReducing Bacteria in Inject Sea Water by “Green” Chitosan/ZnO nanocomposite
More LessOil producing companies utilize water injection as a common oil recovery method for decades, especially for offshore fields, where seawater is typically used as inject water. Due to the size and complexity of the injection system and the high salinity of the water (∼55,000 mg/L); several challenges are faced during this process including microbial growth, fouling and corrosion in the pipeline. Biofilms accelerate corrosion in a biologically conditioned metal–solution interface. Oil producing companies including those in Qatar use biocides to disinfect the water and inhibit biofilm formation caused mainly by sulfate reducing bacteria (SRB). However, traditional biocides may induce bacterial resistance and/or be detrimental to environment. In this study we synthesized chitosan/ZnO nanocomposite (CZNCs) and evaluated its antimicrobial activity against SRB biofilm in inject seawater. CZNCs showed stable behavior when exposed to higher salt concentrations of inject water. The inhibition of SRB activity was concentration-dependent and more than 73% and 43% inhibition of sulfate reduction and TOC removal, respectively, was observed at 250 μg/mL CZNCs at 10% initial ZnO loading. Scanning electron microscopy (SEM) coupled with lactate dehydrogenase (LDH) release assay indicated obvious damages to the cellular membrane which resulted in release of cytoplasmic materials from the bacterial cells. Significant decrease in concentration of EPS extracts was obtained. This work has demonstrated that the exposure of synthesized CZNCs could cause significant SRB anti-biofouling properties. This is the first ever study of antimicrobial potential of chitosan based biocides for SRB inhibition. We are confident that this work will make the scientific as well as the industrial communities to appreciate the application of nanomaterials based biocides. This is the first ever study of antimicrobial potential of any ENM generally, and chitosan based biocides, particularly, for SRB enriched biofilm inhibition. Taking into account tremendous interest to nanomaterials as antimicrobial agents, we anticipate a major impact from a much better material reported in his paper.
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CO2 Utilization through Dry Reforming of Methane Process
Authors: Nimir Elbashir, Shaik Afzal, Debalina Sengupta and Mahmoud El-HalwagiDry Reforming of Methane (DRM) is one of the CO2 utilization processes in which CO2 reacts with methane to produce syngas (a mixture of CO and H2). The DRM process faces 3 major challenges. Firstly, the highly endothermic nature of DRM (ΔH°298 K = 247 kJ/mol) is much higher than that of the conventional Steam Methane Reforming (SMR) which produces a higher quality syngas (higher H2/CO ratio). Secondly, due to low O/C and H/C ratios in the reaction mixture, catalyst deactivation due to coke formation is a major concern for the DRM process. Thirdly, the syngas ratio (H2/CO ratio) obtained from DRM is ≤ 1. This low syngas ratio is only suited for the production of few chemicals and cannot be extended to Fischer-Tropsch process or petrochemicals like methanol. Despite these obstacles, DRM has received a considerable amount of interest by both academia and industry. Using an Optimization approach, this study aims to better understand the CO2 balance of a process incorporating DRM and compare the performance with existing conventional processes. The objective is to ascertain the regions of operation where DRM helps reduce overall CO2 emissions of syngas production. In the first step of the study, all required data pertaining to CO2 emissions related to existing process was collected from various sources. Emission data for oxidant production (steam, oxygen) and upstream emissions for natural gas were taken GREET® software. In the next step, reformer modeling was performed in LINGO® software. A previously developed Gibbs Free Energy Minimization model [1] has been modified to include fugacity coefficients so that equilibrium calculations can be done at 20 bar pressure. Existing processes considered in the study were Steam Methane Reforming (SMR), Partial Oxidation of Methane (POx) and Auto-Thermal Reformer (ATR). These processes mainly differ in the oxidant/methane ratios and steam-to-carbon ratios used. These constraints have been set to simulate industrial reformer conditions. In the cases which involve DRM, 3 cases were used – stand-alone DRM, DRM+SMR in parallel and DRM+POx in parallel. Though CO2 utilization is the main objective of this study, it is essential to note that an objective function only involving CO2 minimization might result in lower syngas production which is undesirable as it directly reduces plant throughput. Hence, an epsilon method approach was used to iteratively reduce the overall CO2 emissions while maximizing overall syngas production. This method was repeated for each syngas ratio for each reformer case. Results indicate that stand-alone DRM helps achieve a near zero carbon footprint but only at syngas ratio close to 1. Combining equally sized DRM with SMR and POx units does not appreciably reduce overall CO2 emissions. The operating costs of reforming networks involving DRM are highly sensitive to the CO2 purification cost. This assessment shows that incorporating a DRM unit directly into any generic syngas production infrastructure does not have an appreciable reduction in CO2 emissions. Nevertheless, there could still be certain special scenarios where DRM helps in achieving the CO2 reduction objective. To investigate this further, case studies have been used to study the CO2 balance for different processing plants utilizing syngas of different H2/CO ratios. Preliminary findings show that in certain specific regions of operation, DRM assisted reforming helps in overall CO2 reduction objective. The operating cost comparison of these options will be the major criterion which will decide the future of these processing options incorporating DRM. REFERENCES [1] M. M. B. Noureldin, N. O. Elbashir, and M. M. El-Halwagi, “Optimization and selection of reforming approaches for syngas generation from natural/shale gas,” Ind. Eng. Chem. Res., vol. 53, no. 5, pp. 1841–1855, 2014. ACKNOWLEDGMENTS This work was supported by Qatar National Research Fund (QNRF), member of Qatar Foundation (NPRP X – 100 – 2 – 024). The statements made herein are solely the responsibility of the authors. The authors would like to appreciate the continuous support of our industrial partner, Total.
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Water Resources and Use in Qatar Prior to the Discovery of Oil
More LessQatar is known as one of the most arid countries in the world with all of the land characterised as dessert which in geographical terms is defined as territory with no surface water. Despite this unpromising situation people have lived on the Qatar peninsula for thousands of years carefully conserving, harvesting and using the scarce water resources. This paper will argue that a better understanding of the conservation and utilisation of fresh water in the past may have implications for the future development of agriculture and water management in Qatar. All the water resources in the past were fed either directly by scarce and sporadic rainfall events or through sub-surface water (fossil water) which formed a fresh water lens floating above a predominantly saline aquifer. The presence of shallow wadis located throughout the country but particularly near the coast are indicative of the occasionally heavy rainfall.This paper will investigate the methods used to provide water to the traditional settlements and more ancient archaeological sites throughout the country. The paper will begin by reviewing the hydrological structure of the Qatar peninsula and its condition prior to the modern over exploitation of water resources from the 1950's onwards. The paper will pay particular attention to the location of settlements around the northern coast where particularly favourable conditions exist as a result of the north Qatar arch. The settlements of the northern coast employed a variety of water catchment methods including modifying shallow natural depressions (rawdhas) to provide either grazing land or in some cases agricultural zones. In some cases such as at Jifara extensive sunken field systems enclosed within mud brick walls were created fed by a series of shallow wells taking advantage of both rainfall catchment and fossil rainwater. In some cases such as at Ruwayda on the north Qatar coast an existing rawdah appears to have been modified to create a garden with trees enclosed by a fortified masonry wall. A variety of well forms were created including shaft wells where water was accessed by buckets or other receptacles lowered by rope (two example of traditional leather buckets with goat hair rope have been found in archaeological excavations in Qatar) and wide shallow stepped wells which allowed direct access to the water either for humans or animals. In the centre of the country access to water has always been more difficult because the freshwater acquifer has been closest to the surface near the coast. As a consequence the majority of human settlement in Qatar has always been close to the coast. Where inland settlement do exist they are usually located either within or next to some geographical feature such as a wadi or a large depression which will act as a catchment area for rainfall. Such settlements are nearly always supplemented with wells which tend to be larger and much deeper than those on the coast. Examples of inland wells include those associated with gardens at Umm Salal Muhammad. The transformation of inland wells with motorised pumps from the 1950's onwards was one of the causes for the depletion and subsequent salinization of the freshwater aquifer in Qatar.In addition to wells and modified rawdahs a number of other forms of water catchment exist. One of the most surprising water sources is the perennial spring (naba‘a) which following periods of heavy or sustained rainfall may result in water literally spring out from the ground. Another unusual source are fresh water springs located off the coast which were traditionally exploited by fishermen and pearl divers. A rare form of water catchment exists in the Jabal Jassasiya rock formations on the north-east coast of Qatar where the natural contours of the rock are modified to form a cistern blocked on one side by a masonry dam. Masonry dams- possibly of medieval date- have also been documented near Umm Salal Muhammad.
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Challenges and Solutions for Treated Sewage Effluent Reuse
The purpose of this work is to identify challenges associated with the treated sewage effluent (TSE) reuse in Qatar and the region. Ultimately this work aims to create a thorough knowledge base for policy makers and end users to maximise the reuse of TSE for non-potable applications. The role of TSE reuse as an alternative source of water supply is well acknowledged in Qatar. TSE generation has increased more than 3.5 times over the past seven years, and it is estimated that the surplus would reach 77 million m3 per year by 2030 [1, 2]. After adequate treatment, TSE can be effectively used for urban, agricultural and industrial applications. The degree of treatment is dictated by the end use water quality requirement. For example, nutrient free TSE is needed for district cooling applications to prevent biological growth within the system, while agricultural applications would benefit from the presence of these nutrients. Presently, district cooling industries use TSE and potable water blend for their operations. For any application, potential wastewater pollutants such as pathogens (e.g. bacteria, protozoa and virus), heavy metals (e.g. lead, mercury, arsenic, and cadmium), nutrients (e.g. phosphorus and nitrogen) and chemical of emerging concerns (Pharmaceuticals, personal care products PPCPs and endocrine disrupting chemicals EDCs) can pose significant threats to living organisms and environment. Currently, the irrigation sector and district cooling industries are the primary users of TSE in Qatar. Considering the potential benefits of TSE reuse in the agriculture sector, a pilot scheme was developed [3] and commissioned targeting the removal of emerging contaminants from TSE. Pilot train includes coagulation, flocculation, sedimentation, advanced oxidation (ozone-peroxide), UV-peroxide, sand filtration, polymer and ceramic ultrafiltration treatment processes. The concentrations of trace elements present in TSE were determined by inductively coupled plasma atomic emission spectroscopy, and the results were compared with the World Health Organization (WHO) and the Food and Agriculture Organization (FAO) reuse guidelines. Moreover, contaminants of TSE that hindered its maximum reuse potential, especially for district cooling applications, were identified by reviewing the make-up and process affected TSE water quality data. Technology screening for removing TSE contaminants was performed by considering water treatment plant footprint and costs. Experimental studies were conducted using coagulation and ion-exchange methods for phosphate removal in TSE for district cooling applications. References: [1] S.Y. Jasim, J. Saththasivam, K. Loganathan, O.O. Ogunbiyi, S. Sarp, Reuse of Treated Sewage Effluent (TSE) in Qatar, Journal of Water Process Engineering 11 (Supplement C) 2016, 174-182. [2] Hajar Farzaneh, Jayaprakash Saththasivam, Kavithaa Loganathan, Oluwaseun Ogunbiyi, Sarper Sarp, and Gordon McKay. (2016). Reuse of treated sewage effluent (TSE) in Qatar and its impact on sustainability and the environment. QScience Proceedings: Vol. 2016, QULSS 2016: Biodiversity, sustainability, and climate change, with perspectives from Qatar, 40. [3] Saad Jasim, Jayaprakash Saththasivam, Kavithaa Loganathan, Advanced Oxidation Processes for Treated Sewage Effluent 2017, Patent application no. PCT/US17/38155.
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Energy Demand Estimation and Forecasting in Qatar
More LessThe economic theory provides a rationale for linking the energy demand to a number of variables that might affect it. Starting from that, the empirical analyses specify a number of alternative specifications of the energy demands (water, electricity and fuel). For instance, Zarnikau (2003) suggests three possible forms. First, a linear specification involving the levels of the variables, where the energy demand is a linear function of production factors or of other elements affecting demand. The second form is still a linear specification, but where the log-levels of the variables replace the levels. These two forms are coherent with production (or consumption) functions being additive or multiplicative, respectively, in the underlying factors. The third case focuses on the share equations, most common in a production-based framework, where the share cost of energy, over the total cost of production, depends on the production factors in a linear fashion. We provide an estimation for energy demand and forecasting. We will use the Auto Regressive Distribute Lag (ARDL) specification. The ARDL model might be estimated again by least squares methods. Notably, this specification allows computing short-run elasticities, the parameters, as well as long-run elasticities, which can be obtained by standardizing the coefficients by the autoregressive polynomial, i.e.. A further advantage of the ARDL specifications comes from their coherence with the existence of a long-run equilibrium relation across the modelled variables. In fact, if we assume that the variables of interest are possibly cointegrated (and are thus non-stationary in their levels) and also characterized by short-term dynamic, we might recast the ARDL model into the so-called Error Correction Model representation (ECM) for the series first difference.The estimation approach of such a model might follow the bounds testing approach to cointegration of Pesaran and Shin (1999) and Pesaran et al. (2001). Despite its appealing form, the ECM representation of the ARDL model is appropriate when only a single cointegration relation exist across the modelled variables. A more general structure is that associated with Vector Error Correction Model (VECM) where the dynamic of a set of variables is jointly estimated. The estimation and testing for cointegration might follow the approaches proposed by Johansen (1988, 1991, 1992, 1994 and 1995). Moving back to the three approaches listed by Zarnikau (2003), we now briefly discuss the estimation of share equations. This approach focuses on the estimation of the share cost of various inputs with respect to the total cost of production for a specific good. We express energy demand as a function of energy prices, the appropriate price should be a weighted average of the prices of the underlying energy sources (electricity, gas, oil…etc.). The weights might be interpreted as share costs, and therefore the approaches for the estimation of share equations turn out to be relevant in this case, see Fuss (1986). Share equations are nothing more than linear equations for the share of the specific energy source on the total energy demand. However, the crucial aspect to be here considered is the presence of constraints: the shares must be positive and must sum up to one. However, various approaches have been proposed to introduce the appropriate constraints, see for instance the methods by Zellner (1962 and 1963). Further, we can take gasoline price as an indicator for energy price in the demand function. We close this set of methodological approaches by taking into account the use of structural time series methods, see Harvey (1989).Such an approach might be extended with the presence of stochastic cyclical and seasonal components and could represent an alternative approach to classical time series methods.Building on an ARDL specification with a latent trend, Dilaver and Hunt (2011a) provide a scenario analysis for Turkey industrial energy demand and Dilaver and Hunt (2011b) analyze scenarios for residential electricity demand in Turkey. Both studies consider three scenarios, the reference one and two opposite cases representing an increase/decrease in the energy demand due to changes in the production levels, the energy efficiency and the prices. Jiang and Li (2012) provide three different scenarios for the evolution of China energy demand starting from a static long-run relation and using scenarios for the underlying factors. Li et al. (2010) analyze the evolution of energy demand and CO2 emissions in Shanghai under two alternative scenarios, one associated with energy conservation policies. Tajudeen (2015) performs a forecast and scenario analysis for aggregated energy demand. He consider three scenarios, the reference one and two alternatives with increases/decreases in the factors affecting energy demand. Zachariadis and Taibi (2015) provide a scenario analysis for Cyprus energy demand based on different projections of underlying macroeconomic factors as well as in terms of energy efficiency improvements.The estimation and the results wil lbe presented in the conference
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Improving Vegetable Crop Production in Qatar: Strategies to determine optimum planting time minimise production risk and maximise water and nutrient use efficiency
Introduction The research developed strategies to be adopted in Qatar to enhance agricultural production and improve the food security situation of the country. The government of Qatar has instituted plans to boost its food security and, as part of the wider food security plan, the country needs improved agricultural technologies and in-country farming techniques to increase crop yields. This QNRF-funded food security project sought to apply innovative technologies and decision support tools to provide strategies for successful vegetable food production on the local Qatari scene. The research has provided methodologies to assist Qatari researchers and Policy makers to make informed decisions about appropriate crops and timing for profitable in-country farming. Rationale The agricultural production problems faced by Qatar are similar to many other arid and semi-arid countries. The challenges faced by Qatar in improving agricultural production represent a wide range of sustainable agriculture issues including limited arable land and water resources, high temperatures associated with high humidity, salinity, plant pests and plant diseases. This research addresses these problems by contributing to the application of innovative ways of maximizing water and nutrient use efficiency for agriculture, and choosing the appropriate planting times for vegetable cultivation. Appropriate preservation of soils for agricultural purposes is not practiced in Qatar. Therefore, this research was carried out to showcase modern technological innovations with the potential to accelerate in-country vegetable production so as to enhance food security in Qatar. Methods The project consisted of four sub-projects, namely Sub-Project 1 (crop management), Sub-Project 2 (soil management and desertification), Sub-Project 3 (financial risk management) and Sub-Project 4 (combination of the three sub-Projects). The respective tasks of the sub-Projects were as follows Sub-Project 1 developed a decision-making framework for sustainable and profitable cropping in Qatar, and used the FAO AquaCrop model to carry out crop growth simulations of cucumber, squash, and tomato (Qatar), and wheat (Australia). Sub-Project 2 utilised the Soil Constraints and Management Package (SCAMP) to assess intrinsic soil and site constraints for sustainable production. The sub-Project also identified several strategies to improve crop productivity. Sub-project 3 derived an integrated drought derivative model that incorporated geo-specific weather factors, crop-growth cycles, and soil management practices to minimize financial risk. Sub-Project 4 combined the climate, crop, soil and financial components to develop an integrated decision-making framework as well as a targeted partner engagement and communication strategy. Results and Discussion The AquaCrop model is recommended for use in simulating yields of crops to assess the effects of agronomic practices including planting dates, soil characteristics, and water/nutrient use efficiency. Months for optimum vegetable planting are September and December. March planting can produce similar yields but more water is required. Because of higher temperatures and greater vapour pressure deficits during the March to June period, field crop yields from these planting dates are highly variable, resulting in very inefficient use of water. It is therefore recommended that planting during this time period in the field should be avoided. It is critically important to maximize water use efficiency in irrigated field crops in Qatar because of the link between water use efficiency and nitrogen use efficiency. It is essential that N fertilizer inputs closely match crop N requirements, and ammonium-based N fertilizers be used in preference to nitrate-N fertilizers. Regular monitoring of the salinity of the irrigation water is required to ensure that it does not exacerbate the current soil salinity status. As nutrient budgets of field-grown squash and tomato have identified a mismatch between nutrient inputs and crop demand in current management practices, the key soil fertility analyses of extractable phosphorus, organic carbon and exchangeable potassium should be undertaken to inform fertilizer management.The Financial Drought model developed using the reconnaissance drought index (RDI) can be used. A policy brief is available on the operation of derivative systems to protect farmers from production risk.The optimization model developed by incorporating a risk measure is recommended for further application. The developed user-friendly output interface for the model can be used for effective application. Significance The project initiated new dialogue between Government and private sector stakeholders in Qatar on food security strategies. Stakeholders were made aware of the lack of current information on the fertility of soils and quality of irrigation water used for vegetable crops in Qatar. The project concentrated on field production of vegetable crops (cucumber, squash and tomato) identified by a preliminary survey of local consumers. Training opportunities were provided for six students in Qatar, Canada and Australia. Results were presented at eight international conferences where QNRF was acknowledged. An analysis of evapotranspiration data for Qatar was conducted and results published. This is the first study of its type for Qatar (Issaka et al. 2017). Conclusions The research has developed a strategy that is in alignment with QNRS Grand Challenge # 1 - Water Security, by focusing on water use efficiency for crop production. It also informs on the optimal times for planting vegetable crops, and reduces fertilizer inputs and costs by avoiding excessive fertilizer use. A key component of the strategy is the need for fertilizer inputs to be closely matched to crop nutrient requirements using a nutrient budget and soil test approach. Regular monitoring of irrigation water salinity is essential to avoid increased salinization. The Financial Drought model will be beneficial in protecting farmers from production risk. Finally, the optimization model will be beneficial in improving farming decisions. Recommendations for Future Research and Development There are major advances in water and nutrient use efficiency that could be applied in both open field and greenhouse agriculture in Qatar, with the objective of making maximum effective use of their very limited water and arable soil resources. Examine how project outputs (AquaCrop/economic and crop selection model, soil / water/ nutrient/ solar radiation use efficiency, communication packages) can be embedded in Qatar's Research and Educational programs. Engage more actively with the Department of Agriculture of the Ministry of Municipality and Environment, and its particular interests in both the broader food security issues, and the tools being offered by the project. Acknowledgement This research was made possible by a NPRP award [NPRP 6-064-4-001] from the Qatar National Research Fund (a member of The Qatar Foundation). The statements in the Report are solely the responsibility of the authors.
References A.K.S. Huda, A.I. Issaka, S. Kaitibie, M. M. Haq, I. Goktepe, A. Moustafa, K. Abdella, M. Pollanen, P.W. Moody, N. Vock, N. Huda, and K.J. Coughlan (2017). Improving Food Security in Qatar: Assessing Alternative Cropping Systems Feasibility and Productivity in Variable Climates, Soil and Marketing Environments (NPRP 6-064-4-001). Final Report, Qatar National Research Foundation, 79pp A. I. Issaka, J. Paek, K. Abdella, M. Pollanen, A. Huda, S. Kaitibie, I. Goktepe, M. Haq and A. Moustafa (2017). «Analysis and Calibration of Empirical Relationships for Estimating Evapotranspiration in Qatar: Case Study.» Journal of irrigation and drainage engineering 143(2): 05016013.
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Dual Stage Pressure Retarded Osmosis: Potential and Applicability
More LessA dual stage PRO process has been proposed for power generation from a salinity gradient across a semi-permeable membrane. Both closed-loop and open-loop dual stage PRO system were evaluated using 2 M NaCl and Dead Sea as draw solutions, whereas the feed solution was either fresh water or seawater. The impact of feed salinity gradient resource and feed pressure on the net power generation and water flux were evaluated. The results showed that power density in stage one reached a maximum amount at, but the maximum net power generation occurred at. This result was mainly attributed to the variation of net driving pressure in stage one and two of the PRO process. The dual stage PRO process was found to perform better at high osmotic pressure gradient across the PRO membrane, for example when Dead Sea brine or highly concentrated NaCl was the draw solution. Total power generation in the dual stage PRO process was up to 40% higher than that in the conventional PRO process. This outcome was achieved through harvesting the rest of the energy remaining in the diluted draw solution. Therefore, a dual stage PRO process has the potential of maximizing power generation from a salinity gradient resource by 20%. DSPRO can be combined with desalination plant using seawater brine as the draw solution either in closed-loop or open-loop. This hybridization has multiple applications such as reducing the impact of discharging concentrated brine to sea, energy storage, and increase the recovery rate of the desalination. Power generation by DSPRO will reduce the energy consumption by the desalination processes. Waste heat from power plants can be used for the regeneration of the draw solution in the closed-loop DSPRO. Process modelling has been performed and shown promising results for DSPRO application for power generation. The impact of module configuration, area and length, with relation to draw solution concentration have shown to have significant impact on osmotically driven processes and should be counted for.
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Accessing dark states optically through excitationferrying states
Authors: Sabre Kais, Zixuan Hu and Gregory S. EngelThe efficiency of solar energy harvesting systems is largely determined by their ability to transfer excitations from the antenna to the energy trapping center before recombination. Dark state protection, achieved by coherent coupling between subunits in the antenna structure, can significantly reduce radiative recombination and enhance the efficiency of energy trapping. Because the dark states cannot be populated by optical transitions from the ground state, they are usually accessed through phononic relaxation from the bright states. In this study, we explore a novel way of connecting the dark states and the bright states via optical transitions. In a ring-like chromophore system inspired by natural photosynthetic antennae, the single-excitation bright state can be optically connected to the lowest energy single-excitation dark state through certain double-excitation states. We call such double-excitation states the ferry states and show that they are the result of accidental degeneracy between two categories of double-excitation states. We then mathematically prove that the ferry states are only available when N, the number of subunits on the ring, satisfies (N = 4l+2, l being an integer). Numerical calculations confirm that the ferry states enhance the energy transfer power of our model, showing a significant energy transfer power spike at N = 6 compared with smaller N values, even without phononic relaxation. The proposed mathematical theory for the ferry states is not restricted to this one particular system or numerical model. In fact, it is potentially applicable to any coherent optical system that adopts a ring-shaped chromophore arrangement. Beyond the ideal case, the ferry state mechanism also demonstrates robustness under weak phononic dissipation, weak site energy disorder, and large coupling strength disorder.
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Modeling Residential Adoption of Solar Energy in the Arabian Gulf Region
Authors: Antonio Sanfilippo, Nassma Mohandes and Marwa Al FakhriModeling the diffusion of residential solar photovoltaic (PV) systems in their social, political and economic context is crucial to help policymakers assess which policies may best support adoption. Current models of renewable energy adoption [1, 2, 3, 4] assume regulatory and incentive frameworks that do not apply to Gulf Cooperation Council (GCC) states, where energy tariffs are strongly subsidized, tax credits are not viable due to the lack of personal income tax, and support for distributed generation through grid access policies such as the Feed-in Tariff and Net Metering is not available. The goal of this study is to address this gap by analyzing the impact of home ownership, the falling cost of PV, the reduction of electricity subsidies, the introduction of a carbon tax, and the diffusion of innovation on the residential adoption of solar PV technologies in Qatar. Our objective is to develop a social simulation platform that helps policymakers and other stakeholders assess the optimal regulatory framework to promote the adoption of building-integrated PV systems in Qatar and other countries which share a similar geographical, political, economic and social context. We present an agent-based model for residential adoption of solar photovoltaic (PV) systems in the state of Qatar as a case study for the Arabian Gulf Region. Agents in the model are defined as households. Each household corresponds to a dwelling in the Al Rayyan municipality of Qatar that is either owned (by citizens) or rented (by expatriates). The objective of the model is to evaluate PV adoption in terms of these two household cohorts under diverse regulatory and incentive scenarios. In the present state of affairs, only Qatari citizens can own property in Al Rayyan and Qatari households are exempt from electricity charges. Therefore, home owners are Qataris who have free electricity, while renters tend to be expatriates who pay for electricity. The more competitive the cost of electricity from residential PV systems is as compared to the electricity tariff, the more likely are household agents to adopt solar PV. Several factors can contribute to make the cost of electricity from residential PV more competitive, including:the falling cost of PV due to increasing technology maturitythe reduction of subsidies for electricity and the gas used for electricity productionthe introduction of a carbon taxthe extension of the electricity tariff to Qatari householdsthe neighborhood effect, which implements peer effects on the diffusion of PV innovation as a percent discount on residential PV cost.We compute solar PV adoption as resource limited exponential growth. Households adopt solar PV with a probability established by the logistic function in (1), where L is a scaling constant, e is the natural logarithm, x is the cost of electricity from residential PV systems and k is a parameter which determines the slope of the adoption curve. We set L = 1 to normalize the output of the logistic function as a probability. For the k parameter, we select a value (k = 0.59) that in the null-hypothesis scenario yields a PV market share that is equivalent to the innovator cohort of adopters in Rogers’ adoption/innovation curve (2.5%) [5]. According to Rogers, “innovators are active information seekers about new ideas”, who are close to the scientific community and other innovators, have financial liquidity, and are willing to take high risks to pursue their vision. The rationale for restricting adopters to innovators in the null hypothesis scenario is that only eco-warriors with financial means and high technology awareness would adopt in the absence of incentives, with high PV costs.(1) f (x) = L / 1+e^( − k∗x) At each simulation tick, each household agent that has not adopted yet, is presented with the opportunity of doing so. Adoption is determined randomly according to the output of the logistic function in (2): a random probability p is generated, and if the probability of adoption as calculated by (1) is greater or equal to p, adoption occurs.We analyze three alternative simulation scenarios:Scenario 1 — Business as usual: no measures are introduced to incentivize PV, the neighborhood effect is active, and the price of PV falls due to increasing technology maturityScenario 2 — 40% of gas and electricity subsidies are curtailed, the neighborhood effect is active, a carbon tax of $8/tCO2e is introduced, the price of PV falls due to increasing technology maturity, and citizens continue to have free electricityScenario 3 — same as scenario 2, with the variant that citizens too pay for electricity. As baseline, we establish a null hypothesis scenario, which is the same as scenario 1, except that the price of PV does not fall due to increasing technology maturity. Details of the simulation results are provided in the attached file to this submission. Our study suggests that Qatar's residential PV adoption is strongly promoted by the falling cost of PV and can be further facilitated through the reduction of electricity subsidies and the extension of the electricity tariff to Qatari households, which are currently exempt. The introduction of a carbon tax can also play a role in accelerating residential PV adoption, if above $8 per metric ton of carbon dioxide equivalent. The ensuing PV adoption rates would help facilitate the national targets of 2% electricity production from solar energy by 2020 and 20% by 2030. References: [1] Zhao, J., E. Mazhari, N. Celik, Y.-J. Son. “Hybrid agent-based simula- tion for policy evaluation of solar power generation systems”. Simulation Modeling Practice and Theory 19, (2011): 2189–2205. [2] Paidipati, J., L. Frantzis, H. Sawyer, A. Kurrasch. “Rooftop photovoltaics market penetration scenarios”. Navigant Consulting, Inc., for NREL: February, (2008). [3] Drury, E., P. Denholm, R. Margolis. “Modeling the US rooftop photo- voltaics market”. In National Solar Conference 2010, 17–22 May 2010, Phoenix, USA, (2010). [4] Graziano, M. and K. Gillingham. “Spatial patterns of solar photovoltaic system adoption: the influence of neighbors and the built environment”. Journal of Economic Geography 15, (2015): 815–839. [5] Rogers, E. M.. Diffusion of innovations. New York, Free Press of Glencoe, RS(N), (2010)
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Novel AGREOR Integration for Enhancing Gas Loading Saving Energy Maximizing Oil Production and CO2 Emissions Mitigation
Authors: Abdukarem Ibrahim Amhamed and Ahmed Mohamed Gamal AbotalebModeling the diffusion of residential solar photovoltaic (PV) systems in their social, political and economic context is crucial to help policymakers assess which policies may best support adoption. Current models of renewable energy adoption [1, 2, 3, 4] assume regulatory and incentive frameworks that do not apply to Gulf Cooperation Council (GCC) states, where energy tariffs are strongly subsidized, tax credits are not viable due to the lack of personal income tax, and support for distributed generation through grid access policies such as the Feed-in Tariff and Net Metering is not available. The goal of this study is to address this gap by analyzing the impact of home ownership, the falling cost of PV, the reduction of electricity subsidies, the introduction of a carbon tax, and the diffusion of innovation on the residential adoption of solar PV technologies in Qatar. Our objective is to develop a social simulation platform that helps policymakers and other stakeholders assess the optimal regulatory framework to promote the adoption of building-integrated PV systems in Qatar and other countries which share a similar geographical, political, economic and social context. We present an agent-based model for residential adoption of solar photovoltaic (PV) systems in the state of Qatar as a case study for the Arabian Gulf Region. Agents in the model are defined as households. Each household corresponds to a dwelling in the Al Rayyan municipality of Qatar that is either owned (by citizens) or rented (by expatriates). The objective of the model is to evaluate PV adoption in terms of these two household cohorts under diverse regulatory and incentive scenarios. In the present state of affairs, only Qatari citizens can own property in Al Rayyan and Qatari households are exempt from electricity charges. Therefore, home owners are Qataris who have free electricity, while renters tend to be expatriates who pay for electricity. The more competitive the cost of electricity from residential PV systems is as compared to the electricity tariff, the more likely are household agents to adopt solar PV. Several factors can contribute to make the cost of electricity from residential PV more competitive, including:the falling cost of PV due to increasing technology maturitythe reduction of subsidies for electricity and the gas used for electricity productionthe introduction of a carbon taxthe extension of the electricity tariff to Qatari householdsthe neighborhood effect, which implements peer effects on the diffusion of PV innovation as a percent discount on residential PV cost.We compute solar PV adoption as resource limited exponential growth. Households adopt solar PV with a probability established by the logistic function in (1), where L is a scaling constant, e is the natural logarithm, x is the cost of electricity from residential PV systems and k is a parameter which determines the slope of the adoption curve. We set L = 1 to normalize the output of the logistic function as a probability. For the k parameter, we select a value (k = 0.59) that in the null-hypothesis scenario yields a PV market share that is equivalent to the innovator cohort of adopters in Rogers’ adoption/innovation curve (2.5%) [5]. According to Rogers, “innovators are active information seekers about new ideas”, who are close to the scientific community and other innovators, have financial liquidity, and are willing to take high risks to pursue their vision. The rationale for restricting adopters to innovators in the null hypothesis scenario is that only eco-warriors with financial means and high technology awareness would adopt in the absence of incentives, with high PV costs.(1) f (x) = L / 1+e^( − k∗x) At each simulation tick, each household agent that has not adopted yet, is presented with the opportunity of doing so. Adoption is determined randomly according to the output of the logistic function in (2): a random probability p is generated, and if the probability of adoption as calculated by (1) is greater or equal to p, adoption occurs.We analyze three alternative simulation scenarios:Scenario 1 — Business as usual: no measures are introduced to incentivize PV, the neighborhood effect is active, and the price of PV falls due to increasing technology maturityScenario 2 — 40% of gas and electricity subsidies are curtailed, the neighborhood effect is active, a carbon tax of $8/tCO2e is introduced, the price of PV falls due to increasing technology maturity, and citizens continue to have free electricityScenario 3 — same as scenario 2, with the variant that citizens too pay for electricity. As baseline, we establish a null hypothesis scenario, which is the same as scenario 1, except that the price of PV does not fall due to increasing technology maturity. Details of the simulation results are provided in the attached file to this submission. Our study suggests that Qatar's residential PV adoption is strongly promoted by the falling cost of PV and can be further facilitated through the reduction of electricity subsidies and the extension of the electricity tariff to Qatari households, which are currently exempt. The introduction of a carbon tax can also play a role in accelerating residential PV adoption, if above $8 per metric ton of carbon dioxide equivalent. The ensuing PV adoption rates would help facilitate the national targets of 2% electricity production from solar energy by 2020 and 20% by 2030.
References
[1] Zhao, J., E. Mazhari, N. Celik, Y.-J. Son. “Hybrid agent-based simula- tion for policy evaluation of solar power generation systems”. Simulation Modeling Practice and Theory 19, (2011): 2189–2205.
[2] Paidipati, J., L. Frantzis, H. Sawyer, A. Kurrasch. “Rooftop photovoltaics market penetration scenarios”. Navigant Consulting, Inc., for NREL: February, (2008).
[3] Drury, E., P. Denholm, R. Margolis. “Modeling the US rooftop photo- voltaics market”. In National Solar Conference 2010, 17–22 May 2010, Phoenix, USA, (2010).
[4] Graziano, M. and K. Gillingham. “Spatial patterns of solar photovoltaic system adoption: the influence of neighbors and the built environment”. Journal of Economic Geography 15, (2015): 815–839.
[5] Rogers, E. M.. Diffusion of innovations. New York, Free Press of Glencoe, RS(N), (2010).
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Estimation of Groundwater Recharge in Arid Regions Using GIS: A Case Study from Qatar
Authors: Husam Musa Baalousha, Nicolas Barth, Fanilo H Ramasomanana and Said AhziAquifers are important sources of water in arid areas, where no surface water exist. Estimation of groundwater recharge from rainfall is a big challenge for hydrogeologists, due to the high uncertainty involved. It is even harder to estimate recharge in arid areas, due to high variability of meteorological parameters in space and time. Unlike recharge in humid and sub-humid areas, recharge in arid areas occurs indirectly after rainfall-runoff accumulates in low lands such as land depressions and recharges the aquifer. A new method for recharge estimation in arid areas has proposed in this study based on soil-water budget model and utilizing geoprocessing tools in GIS. The method uses Digital Elevation Model (DEM), land-cover and rainfall distribution to estimate runoff accumulation in depressions. The soil-water budget model is then applied to estimate the groundwater recharge in areas of runoff accumulation. The geoprocessing tools in GIS such as flow direction and flow accumulation in Spatial Analyst were utilised. The application of the proposed methodology in GIS makes it easy to cover the entire area of study, and to run maps algebra. The method was applied to the entire area of Qatar. The proposed methodology was applied on Qatar as a case study. The spatial resolution of raster maps was 350 by 350 m and the temporal resolution is one day. Data requirements for this study include daily records of rainfall, Digital Elevation Model (DEM) for topography, soil-moisture holding capacity, land-use map and potential evapotranspiration. Recharge is calculated for each cell and summed to provide the total amount. The proposed methodology was applied on the entire country of Qatar using the hydrological year 2013-2014 and daily time steps. This year was selected because enough daily rainfall data was available for this period, with a good coverage of the entire country. Results obtained in this study for the hydrological year 2013/2014 show the total groundwater recharge is approximately 14 million m3, and concentrated more in the northern part of Qatar. The method can be applied on any arid region.
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Vertical zonation and functional diversity of fish assemblages revealed by ROV videos at oil platforms in The Gulf
About one third of the oil and gas extracted worldwide comes from offshore sources. There is currently thousands of large-scale oil and gas platforms spread across the seas and coastal oceans, from the North Sea to the seas of South Asia. Although their primary purpose is not related to enrichment of biodiversity, gas and oil platforms can act as large and complex artificial marine habitats for a wide range of marine organisms, including sessile invertebrates and fishes. These structures have shown to enhance ecosystem function, especially secondary fish production, relative to adjacent natural reefs, besides being among the most productive marine fish habitats globally. Indeed oil platforms constitute important fish aggregating devices, especially in areas subjected to a range of environmental perturbations. Hard substratum availability combined with exclusion zones around these structures allows for the development of diverse fish assemblages. We carried out the first assessment of vertical distribution, diel migration, taxonomic and functional diversity of fishes at offshore platforms in the Arabian Gulf. Video footages were recorded at the Al Shaheen Oil Field, between 2007 and 2014 using a Remotely Operated Vehicle (ROV). Indeed diving and snorkeling are strictly forbidden in the exclusion zone around offshore platforms, precluding conventional monitoring techniques such as underwater visual census, collection of sessile organisms, etc. Routine inspection and maintenance surveys, however, are conducted to monitor the state of underwater structures using ROVs. A total of 4,510 video files, containing 120 hours of underwater video recordings, were provided by Maersk Oil Qatar A/S. These videos were recorded over six years (2007, 2009, 2010, 2011, 2012 and 2014), during day and night, at the 9 platform locations (A-I) within the Al Shaheen Oil Field using a ROV of the model SAAB Seaeye Surveyor Plus 229. To assess the local fish community, a total of 242 videos amounting to twenty-one hours of observation were selected randomly, however, if no fish appear in a selected video a new video was randomly selected from the list. This work represents the first assessment of reef fish communities inhabiting oil and gas platforms in the Arabian Gulf. A total of 12,822 fish, belonging to 83 taxonomic groups were recorded around the platforms. Among them, two species are first recorded for Qatari waters: Cyclichthys orbicularis and Lutjanus indicus. In addition two chondrichthyes, one endangered (Stegostoma fasciatum) and a vulnerable species (Taeniurops meyeni), were also observed across the platforms. Several trends were found in the vertical distribution of the fish community, most species were observed between 20 and 50 m depth and higher fish abundance recorded in the upper layers, down to 40 m depth and decreasing with depth. Vertical variation, however, in fish diversity was generally not accompanied by differences in vertical movements. The vertical variation, however, in fish diversity was not accompanied by differences in vertical movements of the fish. These results suggest that the vertical zonation pattern does not change, or only changes slightly, on a daily basis. The mean centers of mass of the most abundant fish species did not overlap, likely due to potential competition or niche differences. The dominant trophic groups were carnivores and invertivores, being well represented at each depth range (each spanning 10 m) from surface to seabed. Diel vertical movement was observed only for Acanthopagrus bifasciatus, which was concentrated at shallow depths during the daytime but migrated to deeper layers at night. The functional indices showed no significant differences between water depths or diel cycles (day / night). Besides the temperature variation, the reduced light penetration due to platform structures makes difficult the algal growth necessary for browsing herbivorous fish. Thereby, the effect of sunlight penetration may be reflected in the vertical distribution of herbivorous fish, which are rare in deeper layers. Planktivores are densely grouped within and just below the thermocline, which is located around 18 m during summertime. The study demonstrates that oil platforms represent a hotspot of fish diversity and interesting sites for studying fish communities, abundance and behaviour.
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Modeling a regional energy system in a smart city & low emissions perspective: Scenarios for energy transition in Qatar
Authors: Maxime Schenckery, Frederic Babonneau and Alain HaurieThis paper deals with the modeling of a regional energy system, based on the example of Qatar, over a time horizon of 35 years or more, taking into account the possible transition toward a smart city paradigm of the Doha region and the probable climate regime that could result from COP21 and the coming rounds of international climate negotiations. The impact on the energy system of a transition toward smart city could take many forms: (i) by providing two-way communications between consumers and electricity producers, the smart city will foster demand response and distributed energy resource management; (ii) new forms of demand for energy services will materialize in the transport, housing and service sectors that could contribute to lower the environmental footprint of the energy sector; (iii) the smart-grid connection of distributed energy resources and the possibility to provide secondary reserve through grid storage and distributed system service, like e.g. reactive power compensation, will facilitate the penetration of variable renewable energy in the energy system. Qatar is the world-class leader in the export of liquefied natural gas (LNG). It has also access to crude oil reserves. As the economy of Qatar developed, as in other Gulf countries, the energy system expanded assuming an unlimited supply of very low cost fossil fuels. However, the very economic success of the gas and oil exporting countries in the Gulf region is starting to impose a limit on this form of development of the energy system. The share of gas that is used in the region and thus not available for export is increasing sharply. The local pollution due to the burning of fossil fuels in transport, residential, service and industry sectors, has to be curbed. Finally, at COP21 in Paris, more than 160 nations, including Qatar, have agreed to reduce GHG emissions in order to reach a goal of limiting the temperature change at the end of 21st century at 1.5oC. At COP21 Qatar has made a commitment to reduce its per-capita emission level, which is one of the highest in the world. To deal with these challenges, the Gulf countries count on a substitution from fossil fuel source to variable renewable ones (as well as some extent to nuclear power generation in UAE, KSA and Iran). This is exemplified by the location of IRENA headquarters[1] in Abu Dhabi, inaugurated in May 2015. Indeed, harnessing wind and solar energy sources seems promising in the region, with some caveats due to intermittency of wind blowing and sand storms reducing the efficiency of solar panels. There is another game changing phenomenon represented by the drive toward smart cities. The cities in Gulf countries are very modern and they are ready to embrace the smart city paradigm and concept. Abu Dhabi and more generally the UAE, Qatar and Saudi Arabia have announced pilot projects for fully integrated “smart-city” districts. The development of the “internet of things”, which characterizes smart cities, will translate for the energy system into a development of smart-grid connected, distributed energy resources and this should help tremendously the penetration of variable renewable energy sources. The model ETEM-SC[2] used in this research has been designed to help in assessing the policies that could be used to define, up to the horizon 2050, an environmentally friendly energy system in Qatar. ETEM-SC is a technology rich cost-efficiency model, which permits an exploration of the future of the regional energy system under different environmental and economic constraints. The model is derived from the shell-model ETEM (Energy-Technology-Environment-Model), developed at ORDECSYS[3]. This shell has a structure of a linear program, as in MARKAL, MESSAGE or TIMES, with an extensive description of technology and energy choices in the region into consideration. The new additions that have been made for our purpose (SC for Smart Cities) concern: (i) the modeling of constraints and options at the power distribution level, due to the introduction of smart grids, distributed energy resource and demand response; (ii) the consideration of the impact on demand for energy services of the development of a smart city environment, and (iii) the explicit consideration of uncertainty in the scenario building, through the use of stochastic programming and robust optimization techniques. Some technical aspects of these modeling advances have been described in two parent papers (Babonneau et al. (2016a) and (2016b)). The present research will focus on the description of the scenarios for Qatar that result from the use of this model. These scenarios are based on publicly available data and should not be considered as a representation of the energy policy of the state of Qatar. The purpose of this exercise is to demonstrate the potential offered by ETEM-SC to assess the possible penetration of variable renewable energy in regional energy systems with smart-city development, in order to reduce drastically the GHG emissions. [1] The International Renewable Energy Agency. www.irena.org [2] Energy Technology Environment Model-Smart-Cities. [3] See www.ordecsys.com for details.
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Adaptive model of thermal comfort for office buildings in GCC
Authors: Madhavi Indraganti and Djamel BoussaaThe Gulf Cooperation Council (GCC) nations top the world in CO2 emissions/ capita. However, plummeting oil prices and increasing energy demands necessitate rethinking on thermal comfort delivery. This region has warm desert climate throughout. In GCC states, the adaptive comfort standard or the precursor field studies to develop one are non-existent. We carried out thermal comfort field studies in Qatar for thirteen months. In ten typical air-conditioned office buildings, 1175 voluntary subjects completed 3742 questionnaires, while their thermal environments were simultaneously measured. This paper proposes the adaptive model of thermal comfort for GCC. Adopting variable indoor comfort standards that track the outdoor conditions may be effectual in meeting the sustainability goals of the GCC and Qatar Vision 2030.
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Power to the People: A New Trend in Regulation
By Robert HahnSee e.g., https://www.brookings.edu/wp-content/uploads/2017/05/es_20170531_hahnregulation.pdfPower to the People: A New Trend in Regulation Robert Hahn, Robert Metcalfe and Florian Rundhammer* * Mr. Hahn is Professor and Director of Economics at the Smith School, University of Oxford. Mr. Metcalfe is a Postdoctoral Research Scholar at the Becker Friedman Institute, University of Chicago. Mr. Rundhammer is a doctoral student in economics at Georgia State University. We would like to thank Jonathan Ashley, Harry Bush, Paul Joskow, Clement Lapeyre, Stephen Littlechild, Matthew O'Keefe, Cathryn Ross, Anna Rossington, Jon Stern and Dale Whittington for very helpful feedback. This research was funded by Ofwat and by the Smith School at Oxford. The authors, and not the institutions with which they are affiliated, are responsible for the findings of this research and any remaining errors. © 2017 by the authors. All rights reserved. Abstract This paper traces a new development in regulation that encourages utilities to engage more directly with their customers. We make four contributions: First, we perform the most comprehensive analysis to date of how regulators are using customer engagement, and offer a simple model for understanding different customer engagement initiatives. Second, we review assessments of customer engagement. We find that there are no quantitative, empirically robust assessments of the effectiveness of customer engagement as a regulatory tool. Third, we develop two detailed case studies of an energy regulator and a water regulator that are in the forefront of customer engagement efforts. We find that there is no direct link between the engagement strategy used and the economic incentives received by a firm. Finally, we propose a framework for improving the customer engagement process. The new framework relies on microeconomics, modern tools of program evaluation, and supplying the regulated firm with direct incentives to do customer engagement.
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Restoration of saltdegraded marginal lands through cultivation of nutrient enriched quinoa in UAE: impact on growth yield traits and carbon isotope fractionation
More LessQuinoa is an important nutritive crop that can play a strategic role in the development of marginal and degraded lands. Our aim was to evaluate and select superior salt tolerant quinoa genotypes that are well adapted to the UAE climate. We evaluated the carbon isotope composition, seed yield and other agronomical attributes as indicative of the functional performance of quinoa. Field trial was conducted in the hyper dry arid climate in Dubai, UAE and irrigation treatments comprised of saline water with three different salt concentrations (0, 10, 20 dS m-1) during growth and reproductive phase of quinoa. Plant growth, agro-physiological and isotopic composition responses of 6 quinoa genotypes were measured. Significant variations occurred in dry biomass, seed yield, plant height, number of branches, number of panicles, panicle weight, harvest index, N and C content. The stable isotope composition of carbon values varied among quinoa genotypes. Some genotypes produced yields with values significantly greater than 2.04 t ha-1 (Q12), with average increasing to 2.58 t ha-1 (AMES22157). The present study indicated a large variation in Δ values (3.43‰) among quinoa genotypes for salinity treatments and small amplitude of variations was found among the genotypes (0.95‰). Results from the current study showed that Δ might be used as an important selection index for screening and selection the tolerant stable quinoa genotypes that have high iWUE. The data indicate that some genotypes showed higher photosynthetic accimilation traits (ci/ca, iWUE) and were more productive, stable and higher yielder at various salinities. This study provides a reliable measure of specific responses of quinoa cultivars to salinity and it may be valuable in breeding programs. The development of genotypes having both high yield performance and high WUE would be a very useful contribution for producers in the dry regions like Arabian Desert climate.
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Measurements of recycling steel slug at Qatar steel using lowlevel gammaray spectrometry and calculation of risk factors
More LessMeasurements of recycling steel slug at Qatar steel using low-level gamma-ray spectrometry and calculation of risk factors. M.S.Al-Kuwari 1, M. Hushari 2 and K E Hassan3 1Environmental and Municipal Studies Institute, Director 2Radiation and chemical protection department Ministry of environment, Doha-Qatar 3Transport Limited company TRL Correspondent author: Mohammad Hushari, P.O.Box7634 , Doha-Qatar. Tel w :(+974)44139476 Fax (+974)44207000 Mob :(+974)77991059 Email: [email protected]. Abstract Steel slug are final by-products in the steelmaking process pose an environmental hazard for worker near slag dumps. The objectives of the study were the employment of high-resolution low-level gamma-ray spectrometry. The measurements of natural occurring radioactive material (NORM) as well as of the artificial isotope 137Cs, in many types steel slug such as Steel Slag loss aggregate, Asphalt Mix (100% steel slag with 4% Bitumen), slag, 50% Gabbro with 4% Bitumen, and Concrete cube (50% steel slag, 50% gabbro have been done using mentioned γ spectroscopy. The value of NORM material was reduced when they mixed with gabbro. The recycling of slag from the steel production industry is a common practice in all over the world. Slag from integrated steel production plants run by Qatar Steel is processed storage in area not far from the factory. It has therefore been assumed in this study that all slag is storage. Different ratio of steel slag, gabbro and asphalt used in road construction, most of this ratio accepted from radiation risk point of view, but the ratio of 50% of Gabbro and 4% of Bitumen with asphalt used as road base was the most acceptable from regulatory body. Construction of 200 m road was done at Mesaieed city at Qatar its mechanical and strain stress measurements was conducted by specialist in civil engineering, then many core sample from the surface to the bottom of road to measure (NORM) radioactivity have been taken and radiation dose at the site were carried out. The measured activity and hazards indices in asphalt mixing with slag lies within the word permissible values. Thus the used of recycling steel slug can replace at least 50% aggregates in highway construction and concrete
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The Impact of External Shocks on Qatar's GasExport Earnings
By Syed BasherQatar is a high income country ($129,700 GDP per capita), where gas and oil accounts for 92% export earnings of the country. The International market for gas is recently going through a major transformation, with both demand and supply growing from numerous quarters. There is hardly any literature that provides sound empirical and quantitative analysis of such impacts on gas exporting countries. The paper contributes to filling this gap by providing an empirical analysis of how demand, supply, price and related product shock can affect gas export revenue for Qatar using a structural Vector Autoregression (VAR) model. Not all shocks are alike; demand and price shocks have a strong positive impact on Qatar gas export revenue, and a supply shock results in short lasting weak negative impact. A U.S. shale gas production shock leads to a positive persistent effect on gas export revenue of Qatar.
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Dynamic Impacts of Climate Changes and Environmental Sustainability on FoodWater Poverty in a Panel of Selected MENA Countries
More LessKnown to be one of the most arid regions in the world, the Middle East and North Africa (MENA) is particularly vulnerable to climate-induced impacts on water resources and food production. Despite this alarming situation, promoting adaptive governance strategies to deal with such increased hydrological risk remains a low priority for most of political leaderships in the region. It is increasingly clear that adaptation to climate change and environmental sustainability are closely linked to water availability and food production added to a set of social, economic and political factors. In most of the MENA countries, climate change is likely to lead to reduced rainfall and consequently a real threat to food security in what are already dry regions. In certain cases, an intensification of the water cycle has caused more extreme floods and droughts in some countries of the region. Generally, climate change acts as a “threat multiplier” increasing existing vulnerabilities among already vulnerable and poor populations and existing threats to security, and can indirectly rise risks of violent conflict in the region. It is worthy to note that climate impacts will not be equally distributed, and much will depend upon national resources and adaptive capacities which is one of the main focus of the study. Thus, we will attempt to delineate the expected and dynamic impacts of climate change and environmental sustainability on food-water poverty and analyze how the political, economic, and institutional drivers may have shaped governance responses in the region. The linkage between food-water poverty and environmental sustainability hasn»t got a significant policy attraction that generally in favor of livelihood of the poor, which is broadly influenced by climate change, food security challenges and poor access of improved water resources. These challenges and defies commonly encountered by less developing countries, while some MENA countries has no exemption to escape out from this food-water poverty nexus owing to inappropriate socio-economic and environmental action programs of sustainable development. Contrariwise, some others countries in the region, mainly the oil-dependent countries, have been able to overcome such challenges, at least in the short run, primarily thanks to their oil resources and the rent that these generated. In addition, we will endeavor in the current study to examine the dynamic nexus between climate changes, environmental sustainability and food-water poverty in a panel of selected MENA countries over the recent decades. To do this, we will use various empirical models such as pooled least squares regression, pooled fixed effects, and pooled random effects regression techniques. The data on food-water poverty, environmental sustainability and climate changes indicators for the set of selected MENA countries, comprising low and high oil-dependent economies, from 1980 to 2013 are taken mainly from World Development Indicators published by the World Bank (2014) and International Financial Statistics published by the IMF (2014). It»s noteworthy that the considered countries are chosen according to data availability. In order to keep the maximum number of countries possible in the empirical analysis, the forward and backward interpolation technique will be used to fill the gaps between the two periods. In this study, we»ll use five dependent variables (response variables), including three food poverty indicators and two water poverty indicators that were separately regressed with the set of explanatory variables in the panel of the considered countries. These variables were chosen giving their broader coverage of food-water poverty and environmental sustainability indicators in the region. In the empirical analysis, we»ll attempt then to estimate two simple non-linear regression equations, similarly to Ozturk (2017) [1], to understand the food-water nexus, by using a set of explanatory variables of environmental sustainability and climate changes such as the rainfall indicator, the annual average temperature, agricultural value added, forest area, carbon dioxide emissions, GDP per capita, inflation, the consumer price index. Three food poverty indicators will be used as dependant variables, i.e., the depth of the food deficit (kilocalories per person per day), the household final consumption expenditure per capita (constant 2005 US$), and the prevalence of undernourishment (percentage of population). While in the second model devoted to water poverty, percentage of population without access to water sources and percentage of population without access to sanitation facilities will be used as the two dependant variables. The first step is using the conventional panel unit root tests to assess the stationary properties of the selected variables. In this regard, different panel unit root tests will be used to check the order of integration of the given variable»s series. After that, we»ll use the Johansen Fisher panel co-integration tests to evaluate the null hypothesis of no co-integration against the alternative hypothesis of co-integration relationships between variables. In order to get robust inferences, the study will use three separate panel regressions, comprising the panel least squares regression, commonly known as the ‘common constant method’; fixed effects, commonly known as the ‘least squares dummy variables (LSDV)’; and random effects model, commonly known as the ‘Dynamic Model’. The food-water poverty is a buzzword that is generally used by the policymakers to assess the insufficient intake of food calories per day and lack of regular access to water resources among households across countries. In order to understand the food-water poverty nexus in the MENA region, one may look deeply and separately to the main factors that may affect such two linked issues over the time. The real contribution of the study is then to investigate over the high and low oil-dependent countries in the region, the main determinants of food-water poverty that affected mainly by climate changes and environmental sustainability indicators. In this context, it»s substantially required to investigate this relationship for sound policy interventions, in favor of livelihood of the poor and most vulnerable population groups, that should help to reduce the food-water poverty taking into account the most severe challenges facing the majority of countries i.e. climate changes and environmental sustainability. [1] Ozturk, I. (2017). The dynamic relationship between agricultural sustainability and food-energy-water poverty in a panel of selected Sub-Saharan African Countries. Energy Policy, 107, 289-299.
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Emphasizing on the Significance of Safety for Overall Sustainable Development
By Waqas NawazKnown to be one of the most arid regions in the world, the Middle East and North Africa (MENA) is particularly vulnerable to climate-induced impacts on water resources and food production. Despite this alarming situation, promoting adaptive governance strategies to deal with such increased hydrological risk remains a low priority for most of political leaderships in the region. It is increasingly clear that adaptation to climate change and environmental sustainability are closely linked to water availability and food production added to a set of social, economic and political factors. In most of the MENA countries, climate change is likely to lead to reduced rainfall and consequently a real threat to food security in what are already dry regions. In certain cases, an intensification of the water cycle has caused more extreme floods and droughts in some countries of the region. Generally, climate change acts as a “threat multiplier” increasing existing vulnerabilities among already vulnerable and poor populations and existing threats to security, and can indirectly rise risks of violent conflict in the region. It is worthy to note that climate impacts will not be equally distributed, and much will depend upon national resources and adaptive capacities which is one of the main focus of the study. Thus, we will attempt to delineate the expected and dynamic impacts of climate change and environmental sustainability on food-water poverty and analyze how the political, economic, and institutional drivers may have shaped governance responses in the region. The linkage between food-water poverty and environmental sustainability hasn»t got a significant policy attraction that generally in favor of livelihood of the poor, which is broadly influenced by climate change, food security challenges and poor access of improved water resources. These challenges and defies commonly encountered by less developing countries, while some MENA countries has no exemption to escape out from this food-water poverty nexus owing to inappropriate socio-economic and environmental action programs of sustainable development. Contrariwise, some others countries in the region, mainly the oil-dependent countries, have been able to overcome such challenges, at least in the short run, primarily thanks to their oil resources and the rent that these generated. In addition, we will endeavor in the current study to examine the dynamic nexus between climate changes, environmental sustainability and food-water poverty in a panel of selected MENA countries over the recent decades. To do this, we will use various empirical models such as pooled least squares regression, pooled fixed effects, and pooled random effects regression techniques. The data on food-water poverty, environmental sustainability and climate changes indicators for the set of selected MENA countries, comprising low and high oil-dependent economies, from 1980 to 2013 are taken mainly from World Development Indicators published by the World Bank (2014) and International Financial Statistics published by the IMF (2014). It»s noteworthy that the considered countries are chosen according to data availability. In order to keep the maximum number of countries possible in the empirical analysis, the forward and backward interpolation technique will be used to fill the gaps between the two periods. In this study, we»ll use five dependent variables (response variables), including three food poverty indicators and two water poverty indicators that were separately regressed with the set of explanatory variables in the panel of the considered countries. These variables were chosen giving their broader coverage of food-water poverty and environmental sustainability indicators in the region. In the empirical analysis, we»ll attempt then to estimate two simple non-linear regression equations, similarly to Ozturk (2017) [1], to understand the food-water nexus, by using a set of explanatory variables of environmental sustainability and climate changes such as the rainfall indicator, the annual average temperature, agricultural value added, forest area, carbon dioxide emissions, GDP per capita, inflation, the consumer price index. Three food poverty indicators will be used as dependant variables, i.e., the depth of the food deficit (kilocalories per person per day), the household final consumption expenditure per capita (constant 2005 US$), and the prevalence of undernourishment (percentage of population). While in the second model devoted to water poverty, percentage of population without access to water sources and percentage of population without access to sanitation facilities will be used as the two dependant variables. The first step is using the conventional panel unit root tests to assess the stationary properties of the selected variables. In this regard, different panel unit root tests will be used to check the order of integration of the given variable»s series. After that, we»ll use the Johansen Fisher panel co-integration tests to evaluate the null hypothesis of no co-integration against the alternative hypothesis of co-integration relationships between variables. In order to get robust inferences, the study will use three separate panel regressions, comprising the panel least squares regression, commonly known as the ‘common constant method’; fixed effects, commonly known as the ‘least squares dummy variables (LSDV)’; and random effects model, commonly known as the ‘Dynamic Model’. The food-water poverty is a buzzword that is generally used by the policymakers to assess the insufficient intake of food calories per day and lack of regular access to water resources among households across countries. In order to understand the food-water poverty nexus in the MENA region, one may look deeply and separately to the main factors that may affect such two linked issues over the time. The real contribution of the study is then to investigate over the high and low oil-dependent countries in the region, the main determinants of food-water poverty that affected mainly by climate changes and environmental sustainability indicators. In this context, it»s substantially required to investigate this relationship for sound policy interventions, in favor of livelihood of the poor and most vulnerable population groups, that should help to reduce the food-water poverty taking into account the most severe challenges facing the majority of countries i.e. climate changes and environmental sustainability. [1] Ozturk, I. (2017). The dynamic relationship between agricultural sustainability and food-energy-water poverty in a panel of selected Sub-Saharan African Countries. Energy Policy, 107, 289-299.
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Advanced MultiEffect Distillation Plant: Novel Design
More LessThe thermal desalination by Multi-Stage Flash (MSF) and Multi-Effect Distillation (MED) desalination plants are dominantly used in Qatar due to their maturity and reliability in dealing with the harsh seawater conditions of high (TDS, Seawater feed temperature, SDI, and HAB). Realizing the benefits and challenges of the thermal, there is a room of improvement to reduce energy consumption. Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University (HBKU) and Qatar Electricity and Water Corporation (QEWC) took initiative to improve the overall efficinecy and perfomance of thermal deslaintion plants in Qatar. In this work, a novel design and compact MED evaporator will be presented. The expected reduction in heat transfer area will reduce the capital cost of the evaporator as well as the footprint of the MED desalination plant. The present work describes a novel MED evaporator according to the GCC2016-31325 patent. The tubes are arranged in a way to allow generated vapor to flow in a smooth and minimized route to the following effect. The vapor route is designed to avoid shear losses and breakdown of film liquid around the tubes (dry zones) that will eliminate vapor entrainment, which will reduce brine carry over. Since there is no cross flow within tube bundle hence, eliminating the need for demister and vapor boxes. A well-developed Visual Simulation Program (VSP) is used to perform comparison between commercial MED desalination plant (63 MIGD, Rass Laffan, Qatar) and proposed novel design. The evaporator distillate production rate, seawater feed conditions (temperature and salinity), and heating steam conditions are specified as input to the software. The number of effects and the tube specifications are specified as input. The VSP software calculates the required steam consumption flow rate, the heat transfer area for each effect, the condenser and preheaters. The capital cost of the desalination plant was calculated using recent bidding of commercial desalination projects and the updated market material price. Process simulationm shows that, for a given gain output ratio of (GOR = 9), the required heat transfer area of novel evaporator is 20% less than of existing evaporators design due to thermal losses reduction. Moreover, the thermal losses reduction in novel evaporator were calculated via simulation and are in the range of 30% to 60%. Furthermore, removal of demister in novel MED evaporator decreases evaporator width by 65%. However, novel evaporator height is almost 1.25 times of the convnetional. In fact, the novel evaporator cost is 20 % less than that of the convnetional evaporator due to significant reduction of the evaporator width and vapor box. In addition to that, a 3D-CFD simulation have been conducted using COMSOL Multiphysics v.5.2a on the vapor route of the novel MED evaporator, to be compared with that of the convention MED evaporator. The engagement with QEWC to offer a site equipped with seawater intake/outfall, electricity will be highlighted. The detailed design of the pilot test, fabricate, installation, commission of MED pilot test of 25 m3/day at Dukhan will be used to develop the proof of concept.
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Coatings for corrosion protection: What do we need and where are we
More LessCorrosion is the major cause of components, infra structures and equipment failure over the world, affecting seriously various critical sectors, including water and energy security. The direct cost of corrosion may reach 5% of the GDP in some countries, representing an important economic burden for companies and governments. Just to cite an example, operations and maintenance in offshore infrastructures may represent over 50% of the global cost; out of these 80% are due to corrosion. This means that implementation of effective corrosion management strategies is crucial to decrease energy costs, to increase economic competitiveness, to enhance reliability and security and to achieve a more sustainable economy and healthy environment. Concomitantly, countries and decision makers must pay attention to this crucial issue and the existence of dedicated competence centers gathering synergistic efforts to combat corrosion are a step forward to mitigate the problem and to important economic saves. There are very effective corrosion protection solutions that can be put on place. Amongst these multifunctional protective coatings, based on modern nanotechnology approaches, play a pivotal role. Novel functionalities, such as self-cleaning, superhydrophobicity, anti-fouling and self-healing, have been more and more requested in coatings used for corrosion protection of a multitude of materials in a wide array of industrial applications. This trend has imposed many challenges that have been addressed over the last years and that will continue to evolve over the next years, achieving a very high impact on the market. This presentation overviews the impact of corrosion and highlights the relevance of protective coatings to combat corrosion, emphasizing the latest trends on functional coatings and self-healing approaches and its growing use in conventional and new Hi-tech applications. This lecture reviews recent contributions to the field and will provide a critical discussion, identifying successful paths, trends and challenges, answering to important questions “What do we need and where are we?”
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Application of Hydrophobic Membranes for Hydrogen Sulfide Removal from Sour Water
Authors: Joel Minier-Matar, Dareen Dardor, Eman AlShamari, Arnold Janson and Samer AdhamBackground Hydrogen sulfide (H2S) is a highly toxic and corrosive gas generated as a byproduct in both upstream and downstream operations in the oil & gas industry. If H2S is present in water streams, its removal is generally required before water disposal or reuse. At gas processing facilities in Qatar's North Field, wastewater containing H2S, referred to as sour water, is generated during natural gas conditioning and processing. These sour water streams need to be treated before disposal or reuse and that is currently achieved using conventional sour water strippers. With recent advances in membrane materials and fabrication techniques, there is increasing interest from both academia and industry to adopt membrane-based separation processes. For H2S removal from sour water, hydrophobic membranes contactors are believed to be a cost-effective alternative to conventional sour water strippers. In a membrane contactor, the feed stream containing H2S flows on one side of the hydrophobic membrane while a receiving stream flows on the other side. As opposed to other membrane-based processes (e.g. reverse osmosis, microfiltration), the hydrophobic membrane in this application does not perform any selective separation but instead facilitates mass transfer of H2S gas by providing a large surface area to pass through. The receiving solution acts as a trap which also enhance the driving force required to maximize mass transfer. Membrane contactors have been commercially used for the treatment of natural gas but not for sour water. In the past decade, most published literature focused on removing carbon dioxide (CO2) and H2S from natural or flue gas streams. The removal of dissolved gasses such as oxygen and ammonia from aqueous streams has also been studied with successful commercial products and applications. To the author's knowledge, the application of membrane contactors for H2S removal from sour water has not been investigated, which presents the basis for this innovative research. Objectives The overall objective of this project was to evaluate a novel adaptation of membrane contactors for H2S removal from process water generated by onshore gas processing operations located in Ras Laffan Industrial City. A hollow fiber membrane contactor was used to remove H2S from sour water using sodium hydroxide (NaOH) as a receiving solution. The caustic solution immediately reacted with H2S gas converting it into sodium sulfide according to equation 1: H2S+2NaOH –> Na2S+2H2O (1) The rapid conversion of H2S to sodium sulfide in the receiving solution maximized the H2S concentration gradient and hence gas mass transfer through the membrane. Once the sulfide was trapped, ultraviolet (UV) light was applied to oxidize the sulfide to other sulfur species (thiosulfate and sulfate). This oxidation step enabled the receiving solution to be safely disposed, at the appropriate pH, without the risk of H2S release. Methodology A custom-built bench scale unit was used to evaluate H2S removal rates as a function of the feed sulfide concentration, pH and temperature, as well as the sulfide oxidation rate by UV light. For the experiments, a hollow fiber membrane contactor (Minimodule G543, Liqui-Cel, Membrana, 3M Corp., USA) was selected as the separation module and process water collected Qatari gas processing facilities was used as feed solution. The feed water, pretreated to remove suspended solids, had a pH of 8, H2S concentration of 100 mg/L and a total organic carbon content of 60 mg/L. Experimental data were compared with mass transfer equations developed for gas transfer through microporous membrane. Results Results showed that hydrophobic membrane contactors are effective in removing H2S from sour water. The removal rate is directly proportional to the mass transfer coefficient and sulfide concentration in the feed solution. Feedwater pH had an impact on the mass transfer coefficient as well as the removal rate since the H2S speciation in water is pH dependent. At low pH ( < 4.5) the majority of the sulfide was present as volatile H2S gas, enhancing the mass transfer across the membrane. At pH above 8, the mass transfer rate decreased significantly due to the small amount of volatile H2S in solution. Test results indicated that the mass transfer coefficient was proportional to the sulfide speciation in solution. At pH 4, the measured mass transfer coefficient was 0.243 cm/min while at pH 7 it was 0.090 cm/min for experiments performed with actual process water. Feedwater temperature also impacted the mass transfer rate, with higher rates achieved at higher temperatures since the H2S diffusivity increases with temperature. At 45 oC the mass transfer rate was 0.336 cm/min, while at 25 oC was 0.243 cm/min. UV light oxidation experiments showed that sulfide can be converted first to disulfide and then to thiosulfate and sulfate. The conversion from disulfide to thiosulfate is slow when only UV light is used; however, aerating the receiving solution enhances the conversion rate. When UV light alone is used, the oxidation of sulfide to disulfide follows a first order reaction with a rate of 0.015 min-1. When UV was combined with aeration, the oxidation also followed a first order reaction with a rate of 0.035 min-1 (more than 2X higher compared to UV alone), converting the sulfide to thiosulfate and sulfate. Outcome This is the first evaluation of membrane contactors for the removal of H2S from sour water from oil and gas operations. Qatar can be one of the primary beneficiary of this technology since large volumes of sour water are generated during sour gas conditioning and processing in the North Field. This process can also be applied in other operations worldwide and could have a major impact on how sour water is treated in the petroleum industry. The authors had already filled a patent application on this technology (publication # US2016/0355414) and plan to work with the Qatar Science and Technology Park (QSTP) to identify a possible startup company that may be interested in further developing the technology.
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Dead Sea Photovoltaic Plant Expansion With Hybrid Storage System
Authors: Ibrahim George Kiriakos, Wafa Qutaina and Zaher SaafinPalestinian energy sector has a big challenges which arises due to rapid increase in electrical demand, limited in traditional energy sources due to unstable conditions and high cost of fuel used to generate electricity. Recently, implementation of renewable energy resources such as photovoltaic systems (PVs) used as a solution to reduce the prices and utilities dependency on suppliers. There is significant potential for the use of the photovoltaic solar energy in countries like Palestine which receive abundant amounts of solar radiation around the year. The radiation in the surface of the sun 3.838*1023, 1400w/m2 at the boundary of atmosphere and 1000w/m2 as global standard test condition (STC).There are many researches concerning photovoltaic systems executed in Palestine by individuals and utikities, the main projects summarized as follows: 1- Dead sea project: in Jericho, established in 2014 as on land project, with power capacity of 708 KW. 2- JICA project: in Jericho, established in 2012 as on land project, with power capacity of 30KW. 3-Coca Cola Co: in Ramallah, established in 2016 as roof top project, with power capcity of 300KW. 4- Al-AHLI Hospital: in hebron, established in 2015 as roof top project, with power capacity of 200KW. 5- Hebron University: in Hebron, established in 2016 as roof top and on land project with power capacity of 230KW. 6- MLR CO: In Bethlehem, established in 2016 as roof top and on land project, with power capacity of 200KW.This paper dicuss modification of implemented Dead Sea PV project in Jericho (-300 below the sea level, latitude 31.86 and longitude is 35.46) that executed by JDECO company in 2014, with power rating of 708KW, constructed on 10000m2 land and consists of 2360 panel and 13 inverter. The goal of this modification is to increase thw capacity of this station up to 1MW on the available limited area and convert it into hybrid station and to increase the overall capacity of the station from 1200MWH/year to 1801MWH/year.
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Counting the Carbon: Assessing Qatar>s Carbon Dioxide Emissions
Authors: Mona Abdulla AL-Asmakh and Nadya Abdulmonim AL-AwainatiClimate change is the most pressing global environmental issue today, with a potentially devastating impact on human development. According to the Intergovernmental Panel on Climate Change (IPCC) reports, Qatar is ranked as the highest CO2 per capita emitter globally. Qatar is contributing to the reductions of anthropogenic carbon dioxide (CO2) by supplying the world with Liquid Natural Gas (LNG), yet Qatar is being negatively imaged as highest CO2 per capita emitter. The reading of the highest CO2 per capita has affected Qatar's ability to attract green investments and to improve the country's attraction in the tourism market. Qatar's position as the leader CO2 per capita has made it unattractive for investors both internally and externally because of the perception that the investment would not be ‘green’.The per capita emissions are a result of two main factors: the total absolute emissions and the total population. Two major and significant factors, consumption and population, should be taken into consideration when discussing the total absolute emissions for Qatar: The assumption for this equation is that the population uses all the produced energy, which is the denominator. This assumption is a disadvantage to Qatar due both to its low population and the fact that it is an energy producer. CO2emission would be much lower for Qatar if a consumption-based accounting system was used for the calculation of the per capita value. The use of emissions accounting measure is of vital importance to individual countries. There are two feasible carbon emissions accounting units: production-based accounting and consumption-based accounting systems. Production-based accounting is linked to economic system boundaries (greenhouse gas emissions from resident institutional units, analogous to gross domestic product). It involves measuring the emissions occurring within a country's boarder and does not take into account production chains extended across boundaries. An illustration of a production-based system examines the emissions generated from fuel purchases and allocates them the country producing the fuel, not the country consuming the fuel (OECD, 2016). While the Consumption based accounting system is related to how much this country emit for its domestic uses. Data are more difficult to obtain for the consumption-based approach because the computations are more complicated to compile as it relies on input-output tables, which includes all steps in production from raw material extraction through the final assembly and ultimately the final sale of the product (General Secretariat for Development Planning, 2009).The controversy comes in determining responsibility: is it the player initiating the polluting process (consumer) or the player producing the pollution (producer)? Consumption-based measures are preferred by developing countries while production-based measures are preferred by developed countries. Qatar is unfairly portrayed as the highest carbon dioxide emitter in the world in terms of per capita measures. Qatar's carbon footprint takes into account Qatar's energy production rather than the country's domestic consumption. The main argument of the paper is to discuss Qatar's CO2 emissions per capita compared to other reporting measures, and to examine the difference between using a consumption based CO2 emissions accounting system versus a production-based one for Qatar. The paper discusses the complications of using a production-based accounting versus a consumption-based accounting system for Qatar carbon dioxide emissions calculations. The research applies both of Quantitative and Qualitative Analysis. The Quantitative analysis is related to roughly re-estimate Qatar's CO2 Per Capita emissions figure based on Consumption based accounting system. The qualitative analysis focuses on creating different comparisons to compare Qatar's CO2 emissions in terms of different reporting measures to three different categories. First category is comparing Qatar's emissions against GCC countries; These countries have the major common attribute that they are mainly dependent on oil and gas revenues, simlliar demographic location, weather and lifestyle. The analysis outcomes of this catogry illustrates that KSA has the highest emissions for CO2 intensity and for the absolute emissions. The second comparison catogry is comparing Qatar's CO2 emissions against major Liquified Natural Gas (LNG) producers which are Austailia and Malsyisa. This compariisons showed that Australia has the highest emissions of Absolute CO2, CO2intensity as well as the emissions per GDP. The third catogry was to compare Qatar's position related to the major global emitters, such as China, India, Russia, and USA. This comparison resulted in China having the highest absolute emissions, CO2Intensity as well as emissions per GDP. The Analysis outcome of the comparisons highlights that Qatar is not the highest CO2emitter in terms of absolute CO2 emissions, emissions intensity, and emissions per GDP compred to the GCC countries, major LNG producers and the world largest emitters. Qatar has the highest CO2 emissions per Capita due to two main factors: Qatar is the largest LNG producer and Qatar has a relatively small population when comapred to other countries. Qatar is a developing country, it is the largest LNG exporter and it has third highest natural gas reserves in the world. Qatar makes an indirect contribution to mitigating the impact of climate change, which is done though exporting a clean form of energy, i.e., Liquefied Natural Gas. Even though Qatar is a major contributor for the supplying the world with clean energy, Qatar has taken other initiatives to minimize its carbon emissions. Continuous research and development will be a key element to Qatar overcoming the climate change challenges through Research and Development Centres. In summary, the research paper has four main sections. The first section of the paper includes a background on climate change, its impact and mitigations. The second section discusses Qatar's global position using different CO2 emission reporting measures, including Absolute CO2emissions (kt), CO2emissions per GDP (kg per PPP$ of GDP), CO2intensity (kg per kg of oil equivalent energy use), CO2emissions per capita (metric tons per capita). The third part explores Qatar's CO2 per capita calculation incorporating the consumption-based accounting system and assessing the complications of using a production-based accounting versus a consumption-based accounting system for Qatar carbon dioxide emissions calculations. The last section covers Qatar's clean initiatives and offers recommendation towards net zero emissions and improving Qatar sustainability figures.
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Production of hazardous gas sensors using spinel ferrite nanoparticles
More LessThis work reports on sensitive and selective gas sensors based on copper ferrite (CuFe2O4) nanoparticles. The nanoparticles were produced different methods including: colloid microwave assisted hydrothermal method, and co-precipitation method. Those methods enable a precise control of nanoparticle size, The produced nanoparticles were annealed at different temperatures. Structural analysis were carried out using x-ray diffraction (XRD) and transmission electron microscopy (TEM), and they revealed that the as-prepared nanoparticle exhibit cubic structure. The nanoparticles undergo crystal structure transformation to tetragonal structure upon annealing. Furthermore, the nanoparticle were found to grow in size upon annealing. The tetrahedral and octahedral absorption bands which are characteristic of the spinel ferrite were determined using Fourier Transform Infra-Red Spectroscopy (FTIR) measurements. Gas sensors were fabricate by pressing the produced nanoparticle powder into disks. The sensor device was produced utilizing capacitor structure, with the top electrode stainless steel of grid structure. The produced sensors were characterized to be sensitive to both H2S and H2 gases, with greater sensitivity to H2S at low temperatures, where these sensors could detect H2S concentrations of 10 ppm at 80 °C. The low optimal operation temperature reveals the low power requirements for sensor operation. Thus, those sensors exhibit the potential to be used for industrial applications, especially for the petrochemical industry.the Petroleum Institute under a grant number RIFP-14312 and Qatar University
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Effect of Trace 100 vppm H2S on the Corrosion Behaviour of Plain Carbon and Microalloyed Steels in a Predominant Sweet Environment in High Flow Regime
We investigate the effects of the presence of trace (100 vppm) H2S on the corrosion behaviour of plain carbon steel and its various micro-alloyed counterparts in a CO2 saturated (sweet) brine (0.5 M NaCl) environment, in a high flow regime (1000 RPM), at 80oC in a slightly acidic environment (pH 6.6). Potentiostatic current transients indicate that the presence of trace amount of trace H2S in a predominantly sweet regime, where the partial pressure ratio of CO2 and H2S (pCO2:pH2S) is ∼10000:1, shows a very different corrosion behaviour for both plain carbon steels and as well as micro-alloyed steels. In presence of trace H2S, current density starts dropping much earlier compared to H2S free standalone CO2 environment. Trace amount of H2S also induces faster passivation of the corrosion scale, especially for alloys with relatively high Mo (0.7 wt.%) and Ni (1.4 wt.%) content, suggesting that Mo and Ni have a strong effect in presence of trace H2S. On the basis of available literature, we speculate that the effects observed in presence of trace H2S is due to the formation of Mackinawite which forms on the steel surface immediately via solid state reaction and micro-alloying with some specific elements catalyzes the formation of mackinawite and/or assists formation of more stable sulfide phase(s), causing a faster current drop and passivation. Modeling of the hypothesis is currently in progress. Keywords: Micro-alloying, CO2 corrosion, Flow effect, RDE, Plain carbon steel, Cr-Mo-Ni steel. Figure: Potentiostatic current transient for various plain carbon and micro-alloyed steels. Condition - pH: 6.6, Temp: 80oC, Flow: 1000 RPM, @ anodic over potential: Open Circuit Potentials (OCP) +150 mV
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Solar Power Integration with Desalination: A Systematic Assessment of the Potential Environmental Impacts
Authors: Sami G. Al-Ghamdi, Mohamed Alhaj and Ashraf S. HassanConventional seawater desalination processes like the multi-stage flash (MSF) and multi-effect distillation (MED) are environmentally unsustainable. They consume large amounts of fossil fuels which are a major cause of climate change. Further, desalination plants discharge highly concentrated brine which can cause eutrophication and damage the marine life. Qatar, being a country that faces freshwater scarcity, is highly dependent on desalination for municipal water consumption. On average the daily production capacity of all desalination plants in Qatar is 1.5 million cubic meters per day. This incurs heavy costs on both the economy and the environment. It is expected that by 2020, desalination fuel costs will reach $2.55 billion. Conventional desalination can be made more sustainable by integrating it with solar energy. However, assessing the environmental competitiveness of this solution should be done in a systematic way and reflect the overall system performance. Simplistic models like merely calculating CO2 emissions are not enough and only allow for modest conclusions. Based on a previous literature review by the authors, it was found that the MED process with thermal vapor compression (TVC) is an excellent choice to couple with solar thermal energy that is provided from a concentrating solar collector. The authors also developed a configuration for solar-driven MED with TVC that is simpler in component choices and relies 100% on solar energy to provide the superheated steam required for the MED-TVC process. A model was developed for a 7-effect MED-TVC pilot plant and was validated with actual plant data. Current literature on desalination mainly focuses on membrane technologies and almost completely neglects thermal desalination. In the Arabian Gulf region, thermal desalination is predominant and hence it is required to assess its sustainability from a view point and further investigate how coupling renewable energy can reduce the environmental impacts. This work quantifies the environmental impacts of solar desalination in Qatar using life cycle assessment (LCA). Our work is based on the proposed MED-TVC solar-driven plant. The objective of this study is to assist decision making by providing information about the potential environmental impacts of solar desalination, propose system improvements and suggest references for comparison between different renewable energy-driven desalination processes in general. We identified five impact categories: global warming, freshwater eutrophication, water use, mineral resource scarcity and fossil resource scarcity. GaBi tool was used to carry the LCA. Ecoinvent database, GaBi databases, academic literature and expert opinions were used to construct a comprehensive life cycle inventory for the plant. ReCiPe method was used to assess potential impacts in the five categories. This method was used because it includes characterization factors unique to Qatar and also because it was widely used in the literature hence comparisons can be made. The functional unit was 1 m3 of freshwater at the plant. The results of the LCA are then computed, grouped and weighted. Comparisons with similar desalination systems are also made. The findings of this work are highly relevant to Qatar National Vision 2030 as they provide detailed findings on the environmental impacts of solar-desalination which is a promising solution for the problem of water scarcity in Qatar.
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Towards Predictive Reactive Transport Modeling
Conventional seawater desalination processes like the multi-stage flash (MSF) and multi-effect distillation (MED) are environmentally unsustainable. They consume large amounts of fossil fuels which are a major cause of climate change. Further, desalination plants discharge highly concentrated brine which can cause eutrophication and damage the marine life. Qatar, being a country that faces freshwater scarcity, is highly dependent on desalination for municipal water consumption. On average the daily production capacity of all desalination plants in Qatar is 1.5 million cubic meters per day. This incurs heavy costs on both the economy and the environment. It is expected that by 2020, desalination fuel costs will reach $2.55 billion. Conventional desalination can be made more sustainable by integrating it with solar energy. However, assessing the environmental competitiveness of this solution should be done in a systematic way and reflect the overall system performance. Simplistic models like merely calculating CO2 emissions are not enough and only allow for modest conclusions. Based on a previous literature review by the authors, it was found that the MED process with thermal vapor compression (TVC) is an excellent choice to couple with solar thermal energy that is provided from a concentrating solar collector. The authors also developed a configuration for solar-driven MED with TVC that is simpler in component choices and relies 100% on solar energy to provide the superheated steam required for the MED-TVC process. A model was developed for a 7-effect MED-TVC pilot plant and was validated with actual plant data. Current literature on desalination mainly focuses on membrane technologies and almost completely neglects thermal desalination. In the Arabian Gulf region, thermal desalination is predominant and hence it is required to assess its sustainability from a view point and further investigate how coupling renewable energy can reduce the environmental impacts. This work quantifies the environmental impacts of solar desalination in Qatar using life cycle assessment (LCA). Our work is based on the proposed MED-TVC solar-driven plant. The objective of this study is to assist decision making by providing information about the potential environmental impacts of solar desalination, propose system improvements and suggest references for comparison between different renewable energy-driven desalination processes in general. We identified five impact categories: global warming, freshwater eutrophication, water use, mineral resource scarcity and fossil resource scarcity. GaBi tool was used to carry the LCA. Ecoinvent database, GaBi databases, academic literature and expert opinions were used to construct a comprehensive life cycle inventory for the plant. ReCiPe method was used to assess potential impacts in the five categories. This method was used because it includes characterization factors unique to Qatar and also because it was widely used in the literature hence comparisons can be made. The functional unit was 1 m3 of freshwater at the plant. The results of the LCA are then computed, grouped and weighted. Comparisons with similar desalination systems are also made. The findings of this work are highly relevant to Qatar National Vision 2030 as they provide detailed findings on the environmental impacts of solar-desalination which is a promising solution for the problem of water scarcity in Qatar.
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Transmission Grid Topology Control Using Critical Switching Flow Based Preventive Stabilizing Redispatch
Authors: Tian Lan, Wenzong Wang and Garng M. HuangTransmission grid topology control (TC) is an emerging technology proposed in recent years to improve power system performance by using e xisting transmission lines more efficiently. Incorporated into the optimal power flow (OPF) with different objective functions, TC can be used for various purposes, such as operational cost reduction and corrective actions. As a leader of employing TC in the power industry, the Pennsylvania New Jersey Maryland (PJM) Interconnection has identified and published a list of switching solutions for the purpose of thermal limit violation and voltage control. Moreover, with significant penetration of wind and solar generations installed in the grid, the optimal system topology varies with time caused by the uncertainty of intermittent nature. TC has a promising future to track the optimal topology for each hour to reduce the operational cost and the line capacity expansion cost. However, these benefits are only possible if we can overcome the stability issues in operation, which is the focus of our research. A line switching action may introduce a large disturbance in the system and thus transient instability becomes a potential security concern. In previous literature, transient instability is observed in line switching actions in different systems. As a result, some beneficial switching plans are abandoned for the sake of security. Therefore, the key problem is how to enhance system stability to enable beneficial switching actions. To achieve that, a proper index that can be calculated offline and then used online to provide preventive stabilizing control guidelines is desired for TC applications. However, existing indices such as critical clearing time, transient stability index and transient energy function are unsuitable for preventive stabilizing control in TC applications. In addition, these indices are usually used for deterministic studies where the uncertainties in the grid are not considered. In our research work, a new quantitative index, critical switching flow (CSF), is proposed to assess transient stability in TC. CSF is the maximum real power flow allowed on a transmission line so that the system is stable when switching off the line. When a line flow is greater than CSF, the system has a risk of instability when switching off the line. The rigorous mathematical derivation of CSF is provided on a two-machine system and then extended to multi-machine systems. CSF establishes a direct connection between the line flow measurement of a switching target line and system transient stability in TC. Thus, CSF has a natural advantage of providing explicit control instructions in TC over the aforementioned indices. A preventive stabilizing redispatch scheme based on CSF is then proposed to enhance system transient stability in TC applications. First, the CSF values are calculated offline in the day-ahead unit commitment and scheduling stage using our probabilistic algorithm based on PSS/E with precise dynamic models from the industry. The proposed two-stage Monte Carlo simulation algorithm will consider the uncertainties of loads and generations and find the statistically precise CSF, which shows the boundary between stable and unstable switching actions based on the worst scenario. This offline learning process will generate sufficient knowledge for online TC applications. Then, the CSF based preventive stabilizing redispatch scheme will provide control guidelines to find a stable trajectory for an online TC application. Once a switching plan is found unstable in the online stability check, the proposed scheme is carried out first to decrease the line flow to a safe value below the CSF to ensure the stability of the subsequent switching action. The proposed algorithm and scheme are tested on the modified IEEE-118 bus system, which has large scale of wind power and solar power installed. In the numerical studies, the calculated CSF values are valid to avoid all unstable scenarios. Moreover, the proposed redispatch scheme is activated when there are sufficient resources to redispatch and decrease the flow on the switching target line to a value below the CSF. The proposed scheme is activated in 371 out of 800 unstable switching cases in total. All the 371 activated cases are stabilized using our proposed preventive stabilizing redispatch scheme. The proposed scheme will not be activated for the rest of unstable cases because of insufficient resources to redispatch. And details of system response in the proposed scheme are also shown for validation and illustration.
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Fractal Folding to Develop Highly Expandable Multifunctional Lattice Structures
The properties of traditional materials are primarily determined by their atomic or molecular arrangements, which are typically difficult to modify due to constraints on sub-continuum forces in their material lattice and relatively closely packed microstructure. Engineered metamaterials, however, have been shown to allow properties that significantly expand and outperform those of the universe of existing materials. Lattice materials, whose structure is made up through tessellation of a fundamental geometrical unit cell can be seen as analogs of natural crystals and thus serve as an excellent template for metamaterial development. Abundant free space inside cellular structures make imparting real-time geometrical changes in their underlying structure much easier and since the overall properties of lattice materials are directly linked to the geometry of the underlying unit cell, it becomes possible to herald materials capable of reversible change of properties through physical stimuli. In the present work introduce a new class of lattice materials, where a controlled simultaneous folding of the lattice walls results in a significant size reduction while preserving the overall shape of the original lattice. This reversible folding scheme results in 67 and 50% reduction in size at each level for lattices with triangular and square grid topologies, respectively, while the design enables multiple levels of folding to achieve a desired final size. This high degree of geometrical and micro-structural change can yield a correspondingly wide bracket of mechanical and multifunctional behavior. We also study the elastic properties and the phononic band structure of the lattice at different stages of folding, using analytical and finite element methods. This size-changing concept provides an alternate technique for controlling the underlying topology rapidly and reversibly through simple collapse or expansion of the base lattice. Such dramatic change of size points to potential applications for deployable structures, which can simultaneously benefit from the inherent lightweight and multifunctional characteristics associated with lattice architectures.
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A Behavioral Approach to Food Waste Issue in Qatar
Introduction Food and Agricultural Organization (FAO) defines food security as stable access to sufficient, safe, and nutritious food. Food waste is a global and complex problem that affects each of three pillars of sustainable development: environment, economic, and social (FAO, 2013). Food loss is defined as the decrease in quantity or quality of food, whereas food waste is the removal from the food supply chain of food which is fit for consumption, or which has spoiled or expired mainly due to economic behavior, poor stock management, or neglect (FAO, 2014). Food loss occurs upstream of the supply chain, particularly post-harvest losses have drawn attention. On the other hand, food waste is observed more frequently downstream the supply chain, specifically at the retail and consumption stages. The FAO estimates that around one-third of edible parts of the food produced for human consumption in the world get lost or wasted globally, which correspond to about 1.3 billion tons of food per year. Food waste is closely associated with food security as being able to reduce food waste will help feed more people and reduce the pressure on natural resources whilst alleviating the negative impact on environment due to greenhouse gas emissions from food chain operations and loss of biodiversity due to agricultural activities. Especially in developed countries consumers are considered to be one of the main sources of food waste and therefore in the past few years an increasing number of studies has examined food waste and consumer behavior. The food waste cannot be explained by a single behavior, but rather a combination of multiple behaviors that can increase or decrease the likelihood of food being wasted. The aim of this research is to synthesize the existing work on consumers' food waste behavior and to develop a comprehensive conceptual framework and to empirically test this framework with data from a country that is dependent on foreign food imports, leading to growing concerns about food security: Qatar. With an increasing population and the food provision depending on imports that comprise more than 90% of the food consumed in Qatar, food security is a top priority. This paper is a research outcome of the SAFE-Q Project, which aims to contribute to food security efforts in Qatar with a holistic approach to understanding food distribution, food consumption, and food waste. Research Approach Our synthesis of previous work explaining the food waste behavior suggests that the Theory of Planned Behavior (TPB) sets a strong basis for explaining it. The TPB provides a theoretical framework that is commonly used for systematically explaining behavior (Ajzen, 1991). We build a conceptual framework extending the TPB (personal attitudes, subjective norms, perceived behavioral control, intentions, behavior) with six additional constructs identified through our extensive literature review and empirical work in Qatar: motives, financial attitudes, planning routines, social relationships, food surplus, and Ramadan (Aktas et al., 2017). We developed an online questionnaire and collected data from Qatar in English and Arabic. We then used partial least squares structural equation modelling to explain the food waste behavior. Results and Discussion In line with the TPB, we find a negative relationship between perceived behavioral control and intentions, where the perceived behavioral control construct has indicators measuring the “difficulty to control food waste”. The relationship between intentions to reduce waste and the amount of food waste is negative, where we conclude the intentions to reduce waste help reduce the behavior leading to food waste. The positive relationship between personal attitudes and intentions suggest that attitudes towards food waste positively affect the intentions to reduce food waste. We find a strong negative relationship between perceived behavioral control and intentions to reduce waste. When it is difficult to control the food waste, the intentions to reduce it are low. Both food choice motives and financial attitudes positively affect the planning routines. While planning routines help reduce the food surplus, the social relationships construct that reflect hospitality and eating with others result in higher food surplus. A unique finding of our research is that the contextual construct Ramadan is found to be positively associated with food waste behavior. Understanding the contextual variables which affect consumers' food waste behavior could help developing strategies for food waste reduction. The findings reveal the strong impact of changing eating habits during certain periods of the year (Ramadan) and food surplus on food waste behavior. The food surplus as a contributor to food waste is explained by planning routines and social relationships (hospitality, risk averseness towards not having enough, cultural habits around how food is served). Impact and Conclusion Food has a significant role in economic, social, political, and cultural lives. By adopting or avoiding certain behavior patterns regarding food, individuals can contribute significantly to environmental, social, economic, and political sustainability. Therefore, it is important to understand the motivational and structural factors and processes that facilitate or are barriers to reducing food waste behavior. Our research helps increase the awareness around food waste and maybe used as a lever to change consumer behavior towards reducing surplus food at households, which is wasted if not consumed in time. Minimizing the surplus food wasted at the end of the value chain is the most impactful objective since it minimizes the loss of the highest value added after food is grown, harvested, processed, packaged, stored, transported, and distributed. References Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50(2), 179–211. Aktas, E., Topaloglu, Z., Oledinma, A., Sharif, A., Huda, A. K. S., Sahin, H., and Irani, Z. (2017). Contextual Factors Affecting Food Security: A Behavioural Framework. In: The 22nd Logistics Re- search Network Annual Conference and PhD Workshop. 6-8 September, Southampton, UK. FAO (2013). Food wastage footprint. Impacts on natural resources. Summary Report. http://www.fao.org/docrep/018/i3347e/i3347e.pdf Date accessed: 31 October 2017. FAO (2014). Definitional Framework of Food Loss. Working Paper. http://www.fao.org/3/a-at144e.pdf Date accessed: 31 October 2017.
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Comparative Assessment of Conjugated Polymers for High Performance Plastic Electronics
More LessConjugated polymers (CPs) are emerging active materials for electronic and optoelectronic devices, such as organic solar cells, thin-film transistors, light-emitting diodes, as well as optical and amperometric sensors. There has been an intensive worldwide research effort on the development of stable, organic semiconductors as potential replacements for amorphous silicon, the benchmark large area, amorphous semiconductor. ID TechEx, the UK-based market research company, “estimates that over the last two decades global investments into plastic electronics technologies exceed US $10 billion, and predict that this will grow to almost US $25 billion by 2020”.1 The ecological and commercial motivation to implement the use of plastic electronics is compelling. Recently, such efforts have facilitated the development of thin film transistors for backplane applications such as e-paper. The ability to operate in ambient atmosphere without costly and rigorous encapsulation barriers to avoid water and/or oxygen is an important step towards commercialization. Despite ever increasing numbers of newly developed conjugated polymers, the performance of CP thin films in optoelectronic devices prepared by the current fabrication methods has been rather limited largely due to the disordered structure. Liquid crystalline polymers (LCPs) have been widely investigated for various optical, mechanical, and electrical applications due to their unique ordered nature. In general LCP design, rod-like mesogens having a large aspect ratio are connected through somewhat flexible linker units to form a main-chain or as a side chain LCP to a flexible polymer. This design allows good molecular interactions between mesogens, but prevents regularly structured crystal formation. Therefore, it is highly desired to devise a novel and universal molecular design strategy to achieve lyotropic liquid crystalline CPs that can be easily processed to form a macroscopically assembled and aligned structure. The synthesis of well-defined conjugated molecules/polymers is a considerable synthetic challenge that many excellent research groups have addressed over the last decade or so. A particularly promising class of potential donor/acceptor materials for use in organic electronics for solution processed polymers is the promising Indacenodithiophene (IDT) unit. Herein we will report our synthetic efforts in the development of innovative polymeric materials containing a suit of wisely selected side chains and having different bridging atoms by replacing IDT with indacenodithiozole (IDDT) system. When incorporated into small molecules or polymers, this structure affords very narrow band-gaps capable of harvesting a large percentage of the solar flux. References; (1) http://ukplaticelectronics.com, C. G.-U. P. E.
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Fouling assemblages on offshore oil platforms: diverse vertical reefs in the Arabian Gulf
Coral reefs are one of the most biologically diverse and complex marine ecosystems that are being degraded at rapid rates. This consistent steadily trend is especially critical in coastal areas that have experienced an impressive coastal development, as has been occurring in the Arabian Gulf. This Gulf harbours the coral reefs subjected to one of the most extreme environmental conditions worldwide, i.e. high salinities (often >45 psu) and high sea temperatures (> 36° during summer season), together with extensive coastal development that have altered significantly the coastal regions of Bahrain, Qatar and UAE. In these countries most of coastal coral reefs have disappeared throughout the last decades because of habitat loss and alteration; however, offshore coral reefs have been away from these extensive disturbances and they may be considered as regional hotspots of corals. Even, the massive presence of submerged structures from offshore oil and gas platforms needs to be taken into account, since preliminary exploratory field surveys have shown a rich fouling community, dominated by a high variety of sessile groups. Thus, the conservation of coral reefs and associated macroinvertebrates and fish could be enhanced by studying the unexplored artificial reefs that grow attached to submerged structures of offshore oil platforms. This objective is currently being pursued in the framework of the project “Connectivity, diversity and genetic flow between offshore natural coral reefs and oil platforms - NPRP No.: 7-1129-1-201”. We herein analyzed video footages from oil platforms located at the Al Shaheen Oil Field, ca. 90 km offshore NE Qatar. The visual assessment was done by Maersk Oil Qatar in 2014, via a remotely operated vehicle (ROV). The video recordings were done during routine inspections conducted in 20 oil platforms, located at 8 locations. A total of 2000 video files were analyzed to study the relative abundance of Al Shaheen Oil Field's macroinvertebrates, using the CATAMI (Collaborative and Annotation Tools for Analysis of Marine Imagery and Video) classification scheme. This guide has been designed to promote consistency and standards for classifying marine biota and substrata captured in underwater imagery from a broad range of depths (shallow-abyssal) and habitats (temperate reefs, corals, etc.). A total of 17 morphology-based functional groups were identified (Encrusting; Porifera, Octocorallia, Hydrozoa and Bryozoa; Turf: Hydrozoa and Bryozoa; Fleshy arborescent: Antipatharia, and Octocorallia; Hard Coral: Scleractinia; Foliaceous: Hydrozoa and Bryozoa; Barnacle: Cirripedia; Bivalve: Mollusca; Massive simple: Porifera; None Flesh Bushy: Antipatharia, and Octocorallia; Fan Simple: Antipatharia, and Octocorallia; Fan Complex: Antipatharia, and Octocorallia; Whip: Antipatharia, and Octocorallia; Bryozoa: Bryozoa; Anemone: Actiniaria; Unstalked crinoid: Crinoidea; Regular urchins: Echinoidea). The MNCR's (Marine Nature Conservation Review) SACFOR (Superabundant, Abundant, Common, Frequent, Occasional and Rare) semi-quantitative abundance scale was used to study the relative macroinvertebrate abundance. The submerged structures of the oil platforms were studied from 0-60 m depth, divided into 8 depth layers (0-10, 10-20, 20-30, 30-40, 40-45, 45-50, 50-55 and 55-60 m), with time intervals of 30 seconds per layer. PERMANOVA (Permutational Multivariate Analysis of Variance) was used to calculate the similarities among samples using the resemblance of Bray-Curtis similarity. Age and depth were the main factors structuring the sessile macroinvertebrate community in the studied platforms. In contrast, no differences in community structure were found among the platform locations, probably due to the high level of connectivity within the Al Shaheen Oil Field. A total of 8 functional groups contributed >10% to the average dissimilarity of the community (hard coral, fleshy arborescent, foliaceous, encrusting, turf, barnacles, bivalve and massive simple). A clear vertical gradient is apparent for the coverage of epibenthic macroinvertebrates, with diversity and biomass increasing with depth. Encrusting sponges and bryozoans are dominant at shallow depths. Other types of macroinvertebrates become dominant as depth increases, such as foliaceous bryozoans and hydrozans, massive sponges, bivalves, anemones, crinoids and octocorals. Fleshy arborescent octocorals (Dendronephthya sp.) and azooxanthellate scleractinian corals were frequently found on the Al Shaheen oil platforms, at depths greater than 30m. The abundance of both groups tends to increase with depth and the hard corals also tend to be more abundant on older platforms. This study clearly showed that azooxanthellate scleractinian, reef building corals are recruiting and growing on the platforms the Al Shaheen Oil Field, in some cases at high densities. Given that no specimens could be obtained, precise taxonomic identification was not possible, but their morphology suggests they belong to the Caryophylliidae family. This finding is highly significant, given that this type of corals has not previously been reported in Qatari waters. Furthermore, it clearly illustrates the potential of this type of offshore infrastructure to support the establishment of functional reef ecosystems in areas where they are degraded or were previously absent, thus contributing to offset the current net loss of this important type of natural marine habitat.
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Analysis of steam reforming of methane integrated with solar central receiver system
Authors: Haider Ali, Furqan Tahir, Maimoon Atif and Ahmer AB BalochSteam reforming is used for the production of hydrogen or other useful products from hydrocarbon fuels such as natural gas. Reforming is the process in which steam at high temperature reacts with the fossil fuel to form Syngas (CO+H2). The steam methane reformer is widely used in industry for the production of hydrogen. It has the advantage that the energy released from the combustion of hydrogen is almost four times as the energy released from the combustion of methane. In the present study, modeling and analysis of the steam methane reformer is carried out while utilizing the energy via solar tower. In the conventional modeling systems, solar based steam reforming is studied only for a single point in time and the dynamic ?uctuations in the solar energy is not taken into account. Therefore, the performance metrics calculated are not necessarily representative of the actual performance of the solar reforming cycle since the performance will obviously be effected by the amount of solar input. In the work, herein, a solar steam reformer is modeled by considering the real-time data for Direct Normal Incident (DNI) irradiation for the city of Doha. As very high temperature is required for reforming, a solar central receiver tower is incorporated which can achieve high temperatures as much as 1300°C. The solar steam reformer is integrated into a solar receiver tower, surrounded by a field of heliostats, such that the solar is directly irradiating the solar reformer. The steam reformer and solar receiver tower is modeled and in-house code on Engineering Equation Solver (EES) software is written for performing the simulations. The system is analyze based on an annual performance so that the fluctuation of solar supply is taken into account with the cycle performance. The performance of steam methane reformer is studied for three representative days of the year that is 29th April, 15th May and 11th August. The performance characteristics of the steam methane reformer is analyzed in terms of methane conversion (Methane Conversion = (xCO+ xCO2)/(xCO+ xCO2+xCH4), where x is the molar concentration) and molar concentration, while incorporating the solar energy data. For 29th April, the peak incident energy is observed at around 1300 hours and the maximum methane conversion (Methane Conversion = 1) takes place at same time due to high solar irradiation. As for the molar concentration of different species, a maximum hydrogen presence in the peak solar irradiance, and the minimum amount of steam and methane is observed. CO presence tends to increase as well, at solar peak hours whereas the CO2 presence does not vary much and almost remains constant most of the time. Similar trends is observed for 15th May while as for 11th August due to no overcasting and continuous solar irradiance, a smooth trend of solar irradiance and consequently a smooth trend of methane conversion and molar concentrations is observed. The steam methane reformer with the solar receiver tower is effectively converting the methane during the solar hours of day. The study provides information about the performance characteristics of the steam methane reformer.
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Profitability Analysis for a Distributed Grid Connected Photovoltaic System in Qatar
More LessQatar is emerging as one of the most dynamic and innovative economies in the Middle East over the last decades. The rapid expansion in the industrial sector, as the key economic driver, in addition to, the strong growth in construction sector, driven by large government investments, alongside the rapidly increasing population and rising living standards put continuously increasing pressures on domestic energy consumption leading to the escalating demand for electricity. To meet these challenges, Qatar has started thinking for long term plans for reducing it dependency on fossil fuels and implementing energy conservation measures as part of its 2030 National Vision. Therefore, Qatar start investing large amounts of money in supporting research and development in the renewable energy sector, in particular, the photovoltaic (PV) technologies for electricity production due to the high level of insolation resulted from its geographical location in the subtropical ridge. Plans are underway to generate 2% of the national electricity production from solar photovoltaic systems by 2020, and 20% by 2030. Solar PV is one of the four main direct solar-energy technologies, in addition to, the concentrating solar power (CSP), solar thermal and solar fuels. Solar PV has various applications and the majority of the installed PV systems are grid connected either through small-scale rooftop (up to ten kWs) or ground-mounted systems installed on residential or commercial properties (ten kW to one MW), or through utility-scale PV farms (one MW or more). Solar PV systems are being installed everywhere around the globe and in developed countries the fastest growing sector is the distributed, grid-connected, rooftop systems. The motivation for individuals to install their own PV system can vary; early solar adopters chose to own solar PV system because of environmental concerns, or a desire to reduce their reliance on the electric power grid. In recent years due to the rapid decline in PV system installed price, the market for solar photovoltaic systems is growing rapidly into a mature industry welcoming an entirely new class of consumers motivated by the prospect of saving money on their electricity bills and making a responsible investment in their home. The projective of this work is creating a Profitability Analysis Tool (PAT) for PV systems in the context of distributed, grid-connected buildings. An economic evaluation model will be designed to evaluate the electrical energy production from PV systems taking into account all the operational incomes as well as all the expenses for the implementation, operation and maintenance of the PV system during its entire lifetime based on discounted cash flow analysis. The proposed profitability analysis tool will help the investors (home owners) to evaluate their solar PV investment through a wide range of economic inductors such as, Net Present Value (NPV), Internal Rate of Return (IRR), Simple Payback Time (SPT), Benefit to Cost Ratio (BCR) and Profitability Index (PI). The proposed profitability analysis tool gives the investors the ability to investigate different financing methods (combination between equity and debt) in addition to evaluating the advantages of applying different proposed governmental incentives (subsidies and tax incentives). Furthermore, since the variations in discount rate, tariff rate, installation and maintenance cost per kW and solar insolation will have a great impact in the profitability analysis, a sensitivity analysis using Monte Carlo simulation will be included in the proposed profitability analysis tool to highlight the impact of these variations. Furthermore, this Monte Carlo based sensitivity analysis will act as a guide for governmental policy designers to navigate their way to increase distributed solar PV adaptation in Qatar.
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Chitosanbased nanocomposite for the inhibition of sulfate reducing bacteria: Towards “green” biocides for microbial influenced corrosion
Authors: Abdul Rasheed Pathath, Khadeeja Abdul Jabbar and Dr Khaled MahmoudMicrobial Influenced Corrosion (MIC) is a process influenced by various microorganisms especially by sulfate reducing bacteria (SRB) which affects the kinetics of corrosion procedure under anaerobic conditions. About 20% of the annual corrosion damages of metals may be produced by microbial activities especially due to anaerobic corrosion influenced by SRB. MIC is the main contributor of corrosion problems and a leading cause of pipeline failure in oil and gas industries. SRBs are main microorganisms that can anaerobically generate sulfide species causing biocorrosion in the injection networks. Moreover, the produced H2S gas is toxic, corrosive, and responsible for a variety of environmental problems. Additionally, the presence of SRB can result in health and safety risks to workers due to sulfide production. In order to prevent this, oil-producing companies use high concentrations of biocides to disinfect the water and inhibit excessive biofilm formation caused mainly by (SRB). However, traditional biocides may be harmful to environment by forming harmful disinfection byproducts. Also the biocide treatment having other disadvantages like low efficiency against biofilms, release of disinfection byproducts and its high cost. Theses disadvantages can be solved by the use of green biocides including nanomaterials which has very low toxicity, environmental acceptability, safety and ease of use etc. Several nanomaterials have been utilized to inhibit the growth of different microorganisms and can be a possible alternative for controlling SRB biofilm and its corrosion. Here, we introduced an environmentally benign approach to use a green biocide; chitosan-ZnO nanocomposite against SRB induced MIC towards carbon steel. The nanoparticles of chitosan and ZnO were prepared independently and treated together to form the chitosan-ZnO nanocomposite. The nanocomposite was synthesized with different percentage of ZnO initial content and characterized by SEM, TEM, FTIR, TGA etc. The average size of chitosan nanoparticles were in between 40-60 nm and it clearly shows the distribution of ZnO NPs in the chitosan nanoparticles matrix. The particles in chitosan-ZnO nanocomposite were found with almost spherical morphology. The electrodes were made of carbon steel S150 was used for all the experiments. S150 carbon steel electrode of exposed area of 8 mm diameter used for the corrosion experiments after hot mounting process followed by polishing and grinding process. The electrodes were incubated with SRB containing media with and without nanocomposites and kept in a shaking incubator at 37° under inert atmosphere. The effect of the chitosan-ZnO nanocomposite on corrosion inhibition was studied by varying the concentrations of nanocomposites under optimized bacterial concentration and experimental conditions. The surface features and the elemental analysis of the biofilm and corrosion product were evaluated by SEM as well as XPS in different time intervals and compared with the control samples. The surface features of the corroded electrodes was investigated by SEM and profilometry after removing the corrosion product by using a simple chemical treatment procedure. The effect of chitosan-ZnO nanocomposite on corrosion behavior of carbon steel against SRB was investigated by electrochemical impedance spectroscopy, corrosion potential, polarization resistance and polarization curve measurements at different time intervals. It was found that the chitosan-ZnO nanocomposite inhibits the SRB biofilm formation and corrosion. The results of the electrochemical analysis showed that the chitosan-ZnO nanocomposite (10% ZnO content) at 250 ppm concentration having highest corrosion inhibition and can be used an effective corrosion inhibition agent against SRB induced MIC. References Wang, H. F., et al. Materials Chemistry and Physics 124, 791-794, (2010).Vanaei, H. R., et al. International Journal of Pressure Vessels and Piping 149, 43-54, (2017). Xu, D. et al. Engineering Failure Analysis 28, 149-159, (2013).
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