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The Effect of Storing Produced PV Power on the National Grid
Get PDFThe dramatic increase in renewable sources employment and the new trend to eliminate carbon emissions are the main reasons for using energy storage to overcome the fluctuation of Photovoltaic (PV) output. This paper aims to study the ability of PV solar system, to provide a significant fraction of utility systems energy demand in Jordan. MATLAB software was used to simulate algorithms in order to estimate the storage properties of Energy Capacity (EC), Power Capacity (PC), and Capacity Ratio (CR). These properties are mainly affected by the size of the PV system and the flexibility (ff) of the grid. The hourly generation data from the National Electric Power Company (NEPCO) were investigated to determine the most efficient way to feed PV-generated power into the grid.
It was found that for flexibilities (ff) values of 0.7, 0.8, and 1, the No-Dump (ND) PV system, which is the largest PV system that could deliver all its annual production to the grid without any need of spillage of the PV system size were 566.3MW, 998.4MW and 1.6 GW respectively.
Also, the relation between Energy Capacity of storage (EC) and Power Capacity (PC) was investigated, it was found that if storage installed with EC and PC equal to 24 GWh (almost 45% of average daily demand) and 3 GW (which is less than the peak hour demand) at ff=0.8, the penetration of PV energy will increase by 42% of annual demand compared with almost 10% without storage. Furthermore, if ff is increased to 1 in parallel to installing storage with energy capacity and power capacity equal to 52.7 GWh and 4.7GW, respectively, the PV penetration will increase to reach 68% of the annual demand compared to 16% without storage
Comparative Study on Performance of Beam and Arch Bridge Subjected to Uniformly Distributed Load
Get PDFIn this paper, an attempt has been made to study the behavior of beam and arch bridges subjected to static uniformly distributed loads. The target audience of this research paper is Architecture students because they would like to visualize the structural concepts for better understanding with minimal calculation. For this reason, a static load test was conducted on three types of beam bridges and on three types of arch bridges. The performance of the arch bridge is studied by changing the type of beam, and the results are compared with the beam bridge. Based on the test results, it is found that the performance of glued beam bridges is recommended for less span than arch bridges
Study on the Influence Law of Temperature Profile of Vertical Wells in Gas Reservoirs
Get PDFDue to the lack of a robust temperature model and poor knowledge about the influence law of temperature profile, it is still highly challenging to interpret the production profile of vertical wells in layered gas reservoirs from distributed temperature sensing (DTS) quantitatively. In this paper, a coupled temperature prediction model for vertical wells in the layered gas reservoir is developed, considering several microthermal effects and non-isothermal seepage. Based on the theoretical simulation, several single factors' influence on the vertical well's temperature profile in a layered gas reservoir has been analyzed. The sensitivity of temperature profiles on different affecting factors has been evaluated through orthogonal test analysis. It has been found that the influence degree of each factor on the temperature profile of the vertical well in the layered gas reservoir is as follows: formation permeability > production rate >water saturation > wellbore inclination angle > relative density of natural gas > formation thermal conductivity > wellbore diameter (k >Qg > SW > θ > dg > Kt > D). The dominant factors affecting the temperature profile of vertical wells in layered gas reservoirs are formation permeability, production rate, and water saturation. The proposed temperature prediction model can serve as the forward model when developing the inversion system to interpret DTS measurement. The findings of this paper provide solid theoretical support for the quantitative interpretation of the flow rate profile for vertical wells in layered gas reservoirs
FEM for the Acoustic Modeling of Eigenmodes: Case of the Cultural Heritage Monument of Neoria, Crete
Get PDFEigenfrequencies inside a space significantly affect its acoustic characteristics, especially below the Schroeder frequency in the low-frequency range. In Architectural Acoustics, accurate detection and visualization of eigenmodes can be particularly useful in practical applications. One of the most important landmarks in Chania, Greece, is Neoria, a cluster of 16th-century Venetian shipyards. One existing Neoria will be converted and used as a multipurpose hall. For this objective, acoustic modeling and various measurements were performed in the space. One of the purposes of the measures and modeling was the investigation of the eigenfrequencies and the eigenmodes of the area. Finite Element Method (FEM) was used for the acoustic modeling, while the acoustic measurements were performed in various positions according to ISO 3382-1. Impulse responses were measured, and frequency responses of the space were extracted using Fourier analysis. The measurements and the acoustic modeling results show that the frequencies with the most significant effect on the area are 86.1 Hz, 150.7 Hz, and 204.6 Hz. Eigenmodes of the frequencies are visualized with the application of FEM and especially the positions of nodes and antinodes, which can be utilized appropriately for the optimum placement of absorbers and diffusers in the space
Determination of the Effect of Moringa oleifera Seed on the Rheological and Filtration Properties of Water Based Mud
Get PDFA cost-effective and environmentally friendly biodegradable locally sourced alternative will be sought to reduce drilling fluid cost drilling operations. Moringa oleifera seed is a cheap, locally obtainable, and environmentally friendly additive. This study aims to determine the effect and suitability of locally processed Moringa oleifera seed powder (MSP) as an additive to improve the performance of water-based mud. The seeds were collected, prepared, and pulverized to a particle size of 75 microns. Varying concentrations (2.0, 4.0, 6.0, 8.0, and 10.0 g) of the MSP were used to treat a simple mud sample, and their properties were determined at varying temperatures (26°C, 40°C, 50°C, 60°C, 70°C) using American Petroleum Institute (API) standard procedures. Mud samples treated with Carboxymethyl cellulose (CMC) served as control. From the result, it was observed that the pH and the mud weight were not affected by MSP concentration. The mud sample plastic viscosity improved by 18% as MSP concentrations increased. The YP/PV ratios show an enhancement at all Moringa oleifera seed powder concentrations relative to the control mud except for the sharp decrease at 70°C. The test sample processed a greater fluid loss volume and filter cake thickness for all concentrations. The physical examination of the mud filter cake of the additive depicted that they have slippery, smooth, and soft mud cakes. The results elucidated MSP suitability in some traditional chemical materials in the oil and gas industry
Comparison of Plant Trait Biometrics for Paired Invasive and Non-Invasive Species to Magnetized Seed and Watering Treatments
Get PDFA greenhouse study evaluated the widely held hypothesis that invasive plant species have a quicker or stronger response to environmental stimuli such as magnetized irrigation water treatments. A second study objective was to test whether the polarity of magnetized water affected the responses for invasive and non-invasive plant species. Six invasive and six non-invasive plant species were stimulated by magnetizing the seeds followed by applying several magnetized water treatments to the germinated seeds. The species were taxonomically paired then the seeds were exposed to three magnetic field treatments, planted, and irrigated with three magnetized water treatments for approximately two months. The electrical conductivity, oxidation reduction potential (ORP), pH of the water, and nine plant biometrics were measured, collected, and analyzed. The study hypothesis was validated when the invasive species showed enhanced responses to the magnetized seed and water treatments. The invasive species had increased growth in seven out of the nine growth biometrics when exposed to the magnetized seed and water treatments. The long exposure time for pretreatment of seeds (six days) and extended exposure time of the water treatments on the magnets (20 h) contributed to the higher growth rates. The average increase in foliar biomass and leaf area for two paired, invasive species was 184 and 182%, respectively, for the combined seed/watering treatments. In comparison the average increase in foliar biomass and leaf area for two paired, non-invasive species was 88 and 111%, respectively, for the combined seed/watering treatments. The physicochemical water properties for the three magnetized water treatments were correlated with plant growth. The combined magnetic seed/watering treatments produced growth rates that substantially exceeded crop growth rates in comparable magnetized irrigation studies
Influence of Land Tenure on Agroforestry Parkland Phyto-Diversity and Stand Structure in Sudanian Zone of Burkina Faso, West Africa
Get PDFSavanna Zone of Burkina Faso is characterized by the increasing population growth due to human migration from the north and central regions of the country for cultivating agricultural land and pastures. This situation induced land-use changes, and social reorganization has led to new approaches to natural resources management. Tenure issues in natural resources management limit the adoption of agroforestry systems and effective land use scale. This paper describes the species composition, structure, and diversity of woody species on agroforestry parklands at Tiogo under two types of land tenures. Ecological and structural characteristics of vegetation patches were computed to characterize the species composition. A variety of diversity measures were calculated to determine the heterogeneity for each type of land tenure. A total of 49 woody species belonging to 19 families and 38 genera were identified, of which 44 and 48 species were recorded in non-landowners’ farms and landowners' farms, respectively. Leguminosae, Combretaceae and Anacardiaceae were the most abundant families. The dominant species in agroforestry parklands were Vitellaria paradoxa, Parkia biglobosa, Lannea microcarpa, Piliostigma reticulatum and Piliostigma thonningii. Analyses of variance of the entire woody vegetation of agroforestry parklands revealed no significant differences in terms of all computed indexes but showed that the landowners’ farms were the most diverse than non-landowners farms. The density of stems ≥5 cm dbh and the basal area were higher in landowner’s farms than in non-landowners farms. In both types of farms, the size class distributions of the vegetation produced a reverse J-shaped curve, supporting that agroforestry parkland in Tiogo is dominated by young individuals. The spatial distribution of the seedling was mainly clumped, reflecting the dominance of clonal propagation. Security of land and tree tenure is a necessary condition for any land-based investment (planting and protection of preferred species and soil amendment). The challenge to maintain parklands’ tree biodiversity in “good” condition also needs to consider the flexibility of land tenure and equitability sharing of the benefits from trees
Photovoltaic Power Generation Forecasting Based on the ARIMA-BPNN-SVR Model
Get PDFWith the continuous expansion of the capacity of photovoltaic power generation systems, accurate power generation load forecasting can make grid dispatching more reasonable and optimize load distribution. This paper proposes a combined forecasting model based on Auto Regression Integrate Moving Average (ARIMA), back propagation neural network (BPNN), and support vector regression (SVR), namely ARIMA-BPNN-SVR model, aiming at the problem of low accuracy of a single model and traditional forecasting model. Through the complementary advantages of ARIMA, BPNN, and SVR models, the model has good anti-noise ability, nonlinear mapping, and adaptive ability when processing photovoltaic power generation data. Data experiments are carried out on solar photovoltaic power generation in the United States, and the accuracy of model forecasting is evaluated according to MAE, MSE, RMSE, and MAPE. The experimental results show that the proposed ARIMA-BPNN-SVR outperforms the forecasting performance of the single models ARIMA, BPNN, and SVR. Its MAE, MSE, RMSE and MAPE are 0.53, 0.41, 0.64 and 0.84 respectively. In the Wilcoxon sign-rank test, the p-value of the proposed model reached 0.98, indicating the effectiveness of the ARIMA-BPNN-SVR model
On the Linear Stability Problem for a Three-Layer Displacement in a Porous Media
Get PDFIn this paper, we study the secondary oil recovery process. The oil from a porous reservoir at low pressure is pushed by a forerunner, less viscous fluid (a polymer solute). Then the well-known Saffman-Taylor instability appears. Some authors tried to minimize this instability by using a succession of intermediate liquids with constant viscosities - the multi-layer model. The surface tensions on the interfaces between liquid layers are a stabilizing factor. In some previous papers, we proved some contradictions of this multi-layer model. However, we considered that the corresponding stability problem has a solution. This model's first step (and the mathematical basis) is the three-layer model, with a single intermediate liquid. We prove that the linear stability problem for the three-layer model has no solution (in general) - the growth rates of perturbations may not exist. On the contrary, an intermediate liquid with a suitable variable viscosity can almost suppress the Saffman-Taylor instability, even if the surface tensions are missing [17]
Preparation and Characterization of GG-LiCF3SO3-DMSO Gel Polymer Electrolyte for Potential Lithium-Ion Battery Application
Get PDFThis work uses gellan gum (GG) natural polymer as the base polymer to prepare gel polymer electrolytes (GPEs). Lithium trifluoromethanesulfonate (LiCF3SO3) salt is used as a charge supplier, and dimethyl sulfoxide (DMSO) acts as a plasticizer to keep the electrolyte in gel form. Two electrolyte systems are formed, which are LiCF3SO3-DMSO liquid electrolytes and GG-LiCF3SO3-DMSO GPEs. Liquid electrolyte with a composition of 12.42 wt.% LiCF3SO3-87.58 wt.% DMSO (LN3 electrolyte) revealed the highest room temperature conductivity (σrt) of 9.14 mS cm-1. The highest σrt value obtained by the LN3 electrolyte is strongly influenced by the charge carrier concentration (n) relative to the mobility (µ). To form GPEs, GG is added to the LN3 electrolyte since this sample composition gave the highest σrt. The electrolyte of 2.00 wt.% GG-12.18 wt.% LiCF3SO3-85.82 wt.% DMSO (GN3 electrolyte) showed the highest σrt of 9.96 mS cm-1. The highest σrt value obtained by GN3 electrolyte is strongly influenced by µ rather than n. The conductivity-temperature study showed that the increase in conductivity for GG-LiCF3SO3-DMSO GPEs is controlled by an increase in n, not µ. Linear sweep voltammetry (LSV) for the GN3 electrolyte showed high electrochemical stability up to 4.8 V. Cyclic voltammetry (CV) illustrated the redox process in the GN3 electrolyte is reversible. A lithium-ion battery fabricated with GN3 electrolyte showed a good discharge performance up to 480 hours with an average voltage of 1.50 V discharged at a current of 0.001 mA. Based on this work, it can be concluded that natural polymer GG-based GPE has great potential for use in LIBs as a charge transport medium