Control and Optimization of Energy Storage in AC and DC Power Grids

Energy storage attracts attention nowadays due to the critical role it will play in the power generation and transportation sectors. Electric vehicles, as moving energy storage, are going to play a key role in the terrestrial transportation sector and help reduce greenhouse emissions. Bulk hybrid energy storage will play another critical role for feeding the new types of pulsed loads on ship power systems. However, to ensure the successful adoption of energy storage, there is a need to control and optimize the charging/discharging process, taking into consideration the customer preferences and the technical aspects. In this dissertation, novel control and optimization algorithms are developed and presented to address the various challenges that arise with the adoption of energy storage in the electricity and transportation sectors. Different decentralized control algorithms are proposed to manage the charging of a mass number of electric vehicles connected to different points of charging in the power distribution system. The different algorithms successfully satisfy the preferences of the customers without negatively impacting the technical constraints of the power grid. The developed algorithms were experimentally verified at the Energy Systems Research Laboratory at FIU. In addition to the charge control of electric vehicles, the optimal allocation and sizing of commercial parking lots are considered. A bi-layer Pareto multi-objective optimization problem is formulated to optimally allocate and size a commercial parking lot. The optimization formulation tries to maximize the profits of the parking lot investor, as well as minimize the losses and voltage deviations for the distribution system operator. Sensitivity analysis to show the effect of the different objectives on the selection of the optimal size and location is also performed. Furthermore, in this dissertation, energy management strategies of the onboard hybrid energy storage for a medium voltage direct current (MVDC) ship power system are developed. The objectives of the management strategies were to maintain the voltage of the MVDC bus, ensure proper power sharing, and ensure proper use of resources, where supercapacitors are used during the transient periods and batteries are used during the steady state periods. The management strategies were successfully validated through hardware in the loop simulation

Techno-Economic Analysis of Hybrid Renewable Energy Systems for Electrification of Rustic Area in Egypt

Hybrid Power Systems (HPSs), particularly renewable energy-mix systems, use a wide variety of enabling technologies to overcome the difficulties associated with Renewable Energy (RE) resource variability in both standalone and grid-connected systems. According to the Egyptian national program towards reaching the 2020 objectives together with the continuous declination of the RE generation cost, extensive development and deployment of RE are witnessed from the government, academia, utilities and industry in Egypt. Therefore, this paper mainly aims at highlighting the potential of RE-hydrogen concept application for rural electrification in the small villages in Egypt in comparison with batteries. After introducing the comprehensive literature review that demonstrates the advantages and drawbacks of the RE standalone systems that mostly necessitates an Energy Storage System (ESS) support. The optimal.conomic design of the HPS that feeds the required electric load of the small Mansheat Taher village at Beni-Suef Governorate, Egypt is considered. For this purpose, five different HPS configurations are studied such as: PV-wind-battery, PV-Fuel Cell (FC), wind-FC, PV-wind-FC, and PV-wind-battery-FC systems. The models of various systems are optimally designed, sized based on the daily data for energy availability and the demand using HOMERTM software. From the viability analysis of the simulation results, HPS system of xxxxxxx that provides a total net present cost of $1,233,317 is considered the most economic and feasible option. The cost of energy is 0.1424$/kwh with a required initial capital of $916,728. A case study area, Monshaet Taher village at Beni-Suef Governorate, Egypt with (29° 1' 17.0718"N, 30° 52' 17.04"E) is identified for economic feasibility in this work. HOMER optimization model plan was designed with annual average solar radiation scaled of 5.93 (kWh/m2/day), annual average wind speed for the location is 4.92 m/s. Keywords: Batteries, Energy Storage; Fuel Cells; Hybrid System; Renewable Energy; Rural Electrification

Optimum Number of Grounded Shield Wires underneath Extra High Voltage Direct Current Transmission Lines

This paper is aimed at reducing the electric fields underneath extra high voltage direct current transmission lines using grounded shield wires. Two extra high voltage direct current transmission lines are modeled and analyzed. One line is homopolar and the other is bipolar, both are operating at 400 kV. The electric field calculated at the ground surface for the two transmission lines with and without grounded shield wires. In addition, the right-of-way limits for those transmission lines according to the maximum allowable electric field strength are calculated. The charge simulation method is used for calculating electric fields underneath the lines with and without grounded shield wires. A soft computer technique namely genetic algorithm was used also to determine the best location and number of grounded shield wires. The genetic algorithm was applied to a 400kV monopolar dc transmission; the best location of grounded shield wires is at 15m height above ground level for an optimum number of five grounded shield wires at spacing of 6m between them. Keywords: Charge Simulation Method, Electric Field Calculation, Electric Field Reduction, Shield Wires, Direct Current Transmission Lines, Health Effects, Right of Way

A new marketing mix model to rescue the hospitality industry: Evidence from Egypt after the Arab Spring

After January 25th 2011 Egypt witnessed political, economic and social instability leading to drastic consequences in the hospitality and tourism industry. Thus unstable situation reflected on the deteriorated occupancy percentages that led to declined profit margins, higher employee layoffs and degraded quality of product and services. The objectives of this research is to examine how the Egyptian hospitality properties manage this dilemma through their marketing practices, and to propose a new marketing mix model that adds new layers of depth to the traditional marketing mix model. A methodological framework was designed to help in the assessment process of management practices pertaining to marketing initiatives during times of crisis. Results indicated the presence of tactical elements that assembled the traditional marketing mix model in the investigated hotels. However, these elements are not effectively used and the interaction between them not appears very clear. Results also indicated that the new proposed model would help in providing a framework for the Egyptian hospitality industry to maintain their competitive position during crisis time and avoiding undesired situations for labour force and decline of companies׳ revenues.The authors are grateful to the FEMISE (Forum Euro-Mediterranean of Institutes of Economics). This research received financial assistance of the European union in the contest of the FEMISE programme (projectFEM41-04). We are grateful to the anonymous referees of the journal. Earlier version published at the FEMISE International Conference13–14 February2016.The views expressed in this paper are those of the author and do not necessarily represent the MSA University

Topographic attributes control groundwater flow and groundwater salinity of Al Ain, UAE: a prediction method using remote sensing and GIS

In arid regions, over pumping and extraction of groundwater in excess of recharge has resulted sharp depleting in groundwater quantitatively and qualitatively. The effect of topographic attributes on groundwater accumulation and groundwater salinity was investigated in the southwest part of Al Ain, Abu Dhabi using Digital Elevation Model (DEM). Seven topographic attributes, such as topography, slope, aspect, relief, catchment area and drainage network were calculated. The results showed that the area is drained by 3 main basins emerging from Hafeet Mountain and drain southwesterly toward Ain Al Fayda and sand dunes. The results also showed all topographic attributes and hydrological elements are strongly structural controlled by NW and NNE trending fault zones. Spatial correlation was performed to correlate topographic attributes and hydrological data collected from groundwater samples. The result showed strong correlation between flow accumulation and groundwater salinity and topographic attributes and irrigation areas. These findings prove the usefulness of the proposed methods in predicting and identifying sites of high groundwater accumulation and groundwater salinity in arid region. Keywords Hafeet Mountain, Al Ain, UAE, Groundwater, Remote sensin

Induced Pipeline Voltage Near-by Hybrid Transmission Lines

The aim of this paper is to calculate the induced voltage, nearby hybrid transmission lines. Two hybrid transmission lines are simulated and modeled. The first line is double-circuit operating with ac voltage of 220 kV and bipolar circuit with a dc voltage of ±500 kV, while the second line is with flat configuration operating at 500 kV ac and of ±500 kV. The induced voltage on the pipeline is calculated due the mutual effect of the electric field of these lines. The charge simulation technique and COMSOL computer package are used for calculating the electric field underneath the hybrid lines with and without pipelines and are used to determine the induced voltage on the pipelines. The maximum induced voltage is 9.5 kV for the first line at spacing (S) of 10 m and DC circuit height of 15.7 m against 4.3 kV for height of 24.9 m. The corresponding values for the second line at the same spacing S of 10 m are 7.08 and 3.1 kV for DC circuit heights of 19.1 m and 30 m respectively. The maximum induced voltage on the pipeline is slightly changed due to changing the phase sequence of the AC circuit and the spacing between AC and DC circuits. Keywords: Induced Voltage, – Electric Fields, HVDC Transmission, Finite Element Method, Hybrid Transmission Lines

Wild edible tree species in lowland, Ethiopia

Aim of study: to provide baseline information about wild edible tree species (WETs) and their main threats, this will help to develop conservation and management strategies of important species in Ethiopia. Area of study: It focused mainly on dry land part of Ethiopia where information about wild WETs is scanty and their status is unknown under the rampant degradation of the habitats. Main results: documentation of important wild edible tree species, their main uses, and the conclusions related to their status, socioeconomic aspects and conservation needs as well as the factors affecting WETs and the way forward. Research highlights: the study showed a total of 88 WETs and their utilization aspects among different ethnical groups in dry land area of the Ethiopia. Moreover, due to the diversity of WETs and the existing threats, effort has to be done for their future conservation to reach a food security strategy in the country. The associated knowledge with the WETs is also found to be important for the livelihood of the local communities. Thus, this paper can serve as baseline information and indicator for further studies and documentation of WETs in Ethiopia. This could also be useful in other dry land parts in developing countries with similar contexts.Máster en Erasmus Mundus en Gestión Forestal y de Recursos Naturales en el Mediterráneo (MEDFOR

Effects of Age and Season on Serum Testosterone Level in Male Buffaloes

The aim of the present study was to detect the changes occurring in serum testosterone profile in male buffaloes. Thirty blood samples from apparently healthy slaughtered male buffaloes were taken and divided into three age groups, 1.5–1.8, 2 –2.5 and 3–4 years. Scrotal circumference and testicular measurements were conducted and the seminal glands were obtained immediately after slaughter. The fructose content was determined in tissue of seminal gland using spectrophotometer. Our investigations were extended to determine the effect of the seasons on serum testosterone levels (Indoor study). There were significant differences between scrotal circumference, testicular and seminal glands measurements with the age of the animals. There were no significant differences neither between average fructose content of seminal glands (mg/ gland) nor fructose concentration per 1 g. tissue with age, were detected. In addition, it is noticed that the serum testosterone level was higher in the first group (1. 5–1.8 years), then a decline in testosterone levels was recorded from 2.0–2.5 to 3–4 years of age with no significant difference between the different groups. A higher mean testosterone concentration (1.72 ng/ ml) was recorded in autumn, while the lowest average concentration (0.77 ng / ml) was recorded in winter. However, there was no significant difference in testosterone levels between different seasons of the year. Hence, we could suppose that the Egyptian water buffalo bull has no typical breeding season

Relation between Interleukin 8 and Bronchial Asthma in Children: Review Article

Background: Asthma is a frequent respiratory condition to treat. A persistent airway inflammation characterizes this frequent form of pulmonary disease. Immune responses are triggered by cytokines and chemokines produced by airway epithelial cells. Human bronchial epithelial cells secrete IL-8 in response to the presence of interleukin-4 (IL-4) and interleukin-13, both of which are increased in asthmatics. There are two receptors for IL-8, the IL-8 receptor alpha (also known as CXCR1) and beta (also known as the IL-8 RB, CXCR2). IL8 is a potent chemotactic cytokine that activates inflammatory cells by recruiting mast cells, mononuclear phagocytes T lymphocytes, and neutrophils to the site of inflammation. Objective: To determine the relationship between IL8 and bronchial asthma in children. Conclusion: The assessment of IL8 levels in pediatric asthmatic patients is a useful biomarker reflecting the status of asthma and also to glucocorticoids and treatment responses

CASE STUDY AND ANALYSIS Of THE PERFORMANCE OF INDUSTRIAL ACID GAS REMOVAL UNIT(AGRU)AT ELNG (EGYPTIAN LIQUIEFIED NATRUAL GAS) COMPANY THROUGH PROCESS SIMULATION

Acid gas removal process, which is also known as sweetening process, is considered a very important industrial operational process which has taken place in many works. The main idea of this process is based on absorption, and the selection of the solvent is mainly based on its capability of removing acid gases from the feed gas such as carbon dioxide (C02) and hydrogen sulphide (H2S). Such acid gases found in the gas can cause operational problems like corrosion and equipment plugging. The solvent used for the absorption processes to sweeten the natural gas is classified into two types which are chemical and physical absorption. The most used absorption processes for sweetening the natural gas are using the chemical solvents such as alkanolamines or "amine". In this context, diglycolamine (DGA) is used in the aqueous solution to remove the acid gases from natural gas stream. In this research, existing process flow diagram of industrial Acid Gas Removal Unit (AGRU) will be modified in terms of solvent composition· used in the absorption process. Manipulating the ratio of solvent to moisture content in the solvent solution will replace the existing solvent composition. Simulation using Aspen Hysys is then performed to parameters, which are absorption colunm removal efficiency, power consumption, heating duty and cooling duty. The simulation results are expected to show improvement to the existing AGRU system used at ELNG (Egyptian Liquefied Natural Gas Company)