...INTRODUCTION The protection scheme (PS) should be achieved a safe and reliable operation, so that problems are identified. The proposed scheme provides protection to detect any deviations in micro-grid and isolating the smallest possible part, for the rest of the system to continue operating. This protection system also enable micro grid to operate in modes that are associated with the utility grid or islanded provide sufficient security for customers and equipment. The microgrid is connected to the utility grid via a step-up transformer as shown microgrid Figure 1. It has a mesh partially containing Bus_1 and Bus_2. There are two loads connected to the system. This technique employs protection combine symmetrical and differential current components. In microgrid each feeder protected by using two relays that is located at the end of the feeder. In normal...
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...Renewable Energies GEL632 Parts II Tilda AKIKI 1 Part I - Introduction to Renewable Energy Resources Hydrogen Solar and Photovoltaic Geothermal Biomass Ethanol Wind Water / Tides Part II - Modeling converters in microgrid power systems DC/AC inverters DC/DC converters AC/DC rectifiers Part III - Microgrid solar energy systems Photovoltaic power conversion Modeling of a Photovoltaic Module Part IV - Microgrid wind energy systems Wind power - Modeling of induction machines Load Flow Analysis of power grids and microgrids Part V – Solar water heating systems Part VI – Fuel Cells: Components and operation Part VII - Renewable Energy Impacts Methodology of Energy Planning / Life-cycle Analysis / Greenhouse Warming / Ecological Sustainability 2 Part II – Modeling converters in microgrid power systems Single-phase DC/AC inverter with 2 switches (single-phase half-bridge inverter) P: 94 Objective: Convert power from DC to AC at the system frequency of operation. • The PWM (Pulse Width Modulation) technique is used to achieve an AC voltage with a fundamental frequency of 60 or 50Hz. • The two power switches are sequentially turned on an off. • If SW1+ is on, potential in a is the same as potential of the positive DC bus, that is: Van = Vidc. • If SW1- is on, potential in a is the same as that of the negative DC bus, that is: Van = 0. • To generate a time-varying voltage at point a, a sine wave with the desired frequency is compared with a triagular wave to determine the switching...
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...distributed generators is a common feature of all these frameworks. A series of challenges result from this evolution: the need to coordinate distributed participants, the need to harmonize standards and procedures, as well as the need to overcome a series of obstacles to change. This contribution reviews emerging network concepts and the associated challenges. Series compensation, reconfigurable power electronic systems and wide-scale use of phasor measurement units are early examples for these emerging solutions. Index terms – Power transmission, Power transmission planning II. CONCEPTS FOR FUTURE ELECTRICITY NETWORKS A. Microgrids In a system comprising distributed electricity generation, consumers and producers may be located within the same distribution system, reducing the need for long distance transmission. Therefore, the concept of microgrids, i.e. small distribution networks with energy sources and sinks of similar magnitudes has been proposed [1]. These network cells can be operated independently from their superordinated networks. This means that energy balancing, voltage and frequency control can be...
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...Opportunities for Women in Renewable Energy Technology Use in Bangladesh (Phase I) April 2004 Joint UNDP/World Bank Energy Sector Management Assistance Programme (ESMAP) and Bank Netherlands Water Partnership Program (BNWPP) Contents Preface........................................................................................................................vii Abbreviations and Acronyms....................................................................................xi Executive Summary.................................................................................................xiii Background and Context .................................................................................xiii Objectives ....................................................................................................... xiv Coastal Electrification and Women’s Development Microenterprise (CEWDM) ............................................................................................. xv Development of Training Modules ................................................................... xv Operational Performance................................................................................ xvi Social Outcomes............................................................................................. xvi Electrification Options as a Function of Household Income .......................... xvi Costs of Rural Lighting and Electrification.................................................
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...AEG power solutions delivers innovative and highly reliable power solutions associated to outstanding services that meets the demand of today energy supply and prepare tomorrows challenges. AEF power solutions is uniquely positioned to benefit long term from emerging demand for smart microgrids, combined with the increasing need for renewable energy provision that will grow over the coming years. The vision is to become the leader for innovative power management solutions in the green energy revolution. AEG delivers premium power solutions to the world through specific innovation, respect, accountability, reliability and ethical business behavior. Innovation has been the main core of AEG. We are continually seeking new ways to serve customers and conduct business that will benefit and enhance everyone. We are constantly seeking new ideas, methods, approaches and solutions for everyone. We respect everyones needs. We take into account culture, gender, responsibilities, job statues and safety of all cliental. We take responsibility for our actions and will be held responsible for everything we say and do. We respect and will deliver on our commitments. We understand and are committed to respecting the company code and conduct and what it stands for. Company values represents who we are, where we come from and the future we embrace. We will do whatever we can to best serve our consumers. We are here for you and the future of your company. Our number one goal is to...
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...Summary: For the February 14th issue of NAATBatt’s Advanced Battery Weekly, we highlight recent sector activities. The NAATBatt, U.S. and Asia Indices increased 2.7% w/w, 3.8% w/w and 3.2% w/w, respectively. The S&P 500 and Russell 2000 grew 3.3% w/w and 2.2% w/w, respectively. Key Highlights: • Maxwell Technologies announced it is supplying ultracapacitor-based Engine Start Modules (ESM) to Idle Free Systems to provide cranking power for a new anti-idling system. The Work Truck No Idle Heat System™ could provide up to eight hours of interior cab heat with the truck engine turned off. • The Chinese Ministry of Finance in a joint statement with the Chinese National Development and Reform Commission and the Chinese Technology and Industry ministries announced plans to provide more subsidies for electric vehicles (EVs) than previously announced. China will support the promotion of new-energy vehicles in a second batch of cities and regions, including the northeastern provinces of Jilin, Liaoning and Heilongjiang. • XL Hybrids was named by Fast Company publication to its 2014 Ranking of World’s 50 Most Innovative Companies. XL Hybrids was ranked 3rd in the ‘Innovative Companies in Energy’ section trailing Tesla Motors and General Electric. • Sumitomo has developed and installed a large-scale power storage system that utilizes used electric vehicle (EV) batteries. The commercial scale storage system, built on Yume-shima Island, Osaka, will begin...
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...Grid Energy Storage U.S. Department of Energy December 2013 Acknowledgements We would like to acknowledge the members of the core team dedicated to developing this report on grid energy storage: Imre Gyuk (OE), Mark Johnson (ARPA-E), John Vetrano (Office of Science), Kevin Lynn (EERE), William Parks (OE), Rachna Handa (OE), Landis Kannberg (PNNL), Sean Hearne & Karen Waldrip (SNL), Ralph Braccio (Booz Allen Hamilton). Table of Contents Acknowledgements ...................................................................................................................................... 1 . Executive Summary ....................................................................................................................................... 4 1.0 Introduction .......................................................................................................................................... 7 2.0 State of Energy Storage in US and Abroad .......................................................................................... 11 3.0 Grid Scale Energy Storage Applications .............................................................................................. 20 4.0 Summary of Key Barriers ..................................................................................................................... 30 5.0 Energy Storage Strategic Goals ...............................................
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...Electrical services design Institution Student name Introduction The need for electricity has been ever increasing. As well, the numbers of critical or sensitive loads have also increased. Today, the electricity transmission and distribution is greatly affected by this ever growing need. On the other hand, the consumer's demand has also been in a rising manner. These problems can be catered for by the use of energy storage devices, renewable energy and use of distributed generation. Micro-grid paradigm can deal effectively with the ever increasing electricity needs. This paradigm is bestowed with the ability to regulate the electricity flow. This is achieved through the generation and distribution mechanisms. Grid refers to different interconnection of different electricity transmission lines. The line does not necessarily need to be transmitting electricity of equal magnitudes. But the electricity of different magnitude that runs from the highest to the lowest magnitude possible. In short, the grid connects the consumers to the electricity supply utilities (Vittal & Ayyanar, 2013, pg. 162). The renewable energy integration into the main grid can take place in the distribution or at the transmission levels. The point at which integration takes place depends on the size or the scale of the electricity generation. Large generating stations directly feed the main grid. Unlike large generating stations, the small distributed generations feed the low or medium voltage lines...
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...Energy Storage Moves Wind to Baseload Power LONDON -- The key to further wind sector success may be the ability to provide baseload power. New solutions based on lithium batteries can deliver convincing foundations to balance wind's variability. For more than two decades, practitioners have been developing control solutions to make operating wind energy plants more efficient. One of the latest projects commissioned by a Chinese operator was dedicated to energy storage. In China, feed-in regulations stipulate that 10 percent of the power installed from wind energy plants must be available via energy storage at any time for two hours. Norbert Hennchen, managing director of Freqcon in Walsrode, Hannover, Germany says lithium batteries possess the greatest technological potential with regards to saving energy, and therefore the ability of renewable energy sources to provide baseload power. The topic of storing renewable energy is currently on trend and is being discussed and implemented on many fronts. Energy density plays a big part in this. Pumped storage plants deliver approximately 0.5 kWh/m3 from an assumed drop height of 200 metres; in contrast, hydrogen plants deliver 500-2300 kWh/m3. With the latter, however, the efficiency of the energy supply is comparably low. Lithium battery systems are right in the middle, achieving approximately 125-400 kWh/m3 - and up to 2500 kWh/m3 under laboratory conditions. When on the subject of efficiency, Hennchen's eyes light up: "Such...
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...1990 Interruptible load considerations in spinning reserve assessment of isolated and interconnected generating systems Chowdhury, N.; Billinton, R.; Power Syst. Res. Group, Saskatchewan Univ., Saskatoon, Sask. This paper appears in: Generation, Transmission and Distribution, IEE Proceedings C Issue Date: Mar 1990 Volume: 137 Issue:2 On page(s): 159 - 167 ISSN: 0143-7046 INSPEC Accession Number: 3606872 Date of Current Version: 06 å «æ 2002 Abstract The authors present a technique which includes interruptible loads in the probabilistic assessment of the operating reserve in isolated and interconnected generating systems. This technique is then used to evaluate the magnitude and corresponding maximum allowable time delay of load interruption required to reduce the unit commitment risk in the absence of other capacity adjustments. They also present a probabilistic technique which can be used to evaluate the inherent interruptible load carrying capability of an isolated and interconnected generating system which exists without having to commit any extra units other than those required to carry the firm load. The study provides an insight into load interruption and its effect on the system risk. The techniques developed are illustrated by numerical examples. These techniques can be used in short and medium term operational planning Electric Power Systems Research Volume 18, Issue 2, March 1990, Pages 99–103 Microprocessor based on-line assessment...
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...Exploring the imperative of revitalizing America’s electric infrastructure. the SMART GRID: an introduction. How a smarter grid works as an enabling engine for our economy, our environment and our future. prepared for the U.S. Department of Energy by Litos Strategic Communication under contract No. DE-AC26-04NT41817, Subtask 560.01.04 DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor Litos Strategic Communication, nor any of their employees, make any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer or otherwise does not necessarily constitute or imply its endorsement, recommendation or favoring by the United States Government or any agency thereof, or Litos Strategic Communication. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. PRINTED IN THE UNITED STATES OF AMERICA. PREFACE It Is A ColossAl tAsk. But It Is A tAsk thAt must BE donE. The Department of Energy has been charged with orchestrating the wholesale modernization...
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...Renewable Energy Resources or Fossil Fuels: Global Warming, Efficacy and Cost Jeneen Rybak English Composition II Professor Sharon Carmack December 27, 2012 Throughout history, people have consistently developed a more convenient way to manage daily life. They have created ways to have access to fresh clean water, systems to remove human waste from within the home, heat, transportation, and electricity. People have become accustom to convenience, without thinking about the damage they could be causing to their own environment. It has become apparent that the human race has inadvertently and irreversibly caused damage to the very environment they depend on. Most of this damage is in our atmosphere due to the use of fossil fuels and the emission of carbon dioxide. Now is the time for the U.S Environmental policy to focus on developing renewable energy resources rather than further developing more oil resources. Global warming can be seen in numerous different forms, including severe weather patterns, changing seasons and melting glaciers. Since 1912, the Kilimanjaro snows have melted more than 80 percent and the glaciers of the Himalaya in India are retreating so quickly that researchers believe they could completely disappear by 2035. Even the migration pattern of animals and insects has changed with the rising temperatures (Glick, 2004). Though the cost of renewable energy sources may be slightly higher than oil (Rangarajan, & Guggenberger...
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...Available online at www.sciencedirect.com Solar Energy 98 (2013) 167–179 www.elsevier.com/locate/solener Ensuring long term investment for large scale solar power stations: Hedging instruments for green power A. Radchik a,⇑, I. Skryabin b, J. Maisano c, A. Novikov d, T. Gazarian e Mathematics & Statistics, Faculty of Science, UTS and Director GTS Pty. Ltd., Suite 2, 16 Figtree Avenue, Randwick, NSW 2031, Australia b Centre for Sustainable Energy Systems, Australian National University, Canberra 2000, Australia c Energy Markets, TTA Pty. Ltd., Suite 12, L6, 321 Pitt St., Sydney, NSW 2000, Australia d School of Mathematics & Statistics, Faculty of Science, University of Technology Sydney (UTS), P.O. Box 123, Broadway, NSW 2007, Australia e School of Mathematics & Statistics, Faculty of Science, UTS, 1 Stella Vista Pl, Greenwich, NSW 2065, Australia Available online 29 March 2013 Communicated by: Associate Editor Frank Vignola a Abstract There is a general consensus that solar power is one of the cleanest energy technologies available. Nevertheless, investment in largescale Solar Power Generators (SPGs) is largely impeded by the intermittent nature of solar power. Since the electricity market has a critical responsibility to maintain the reliability of energy supply, the SPG can be registered only as the market semi-scheduled generator (AEMC, 2011). This option excludes the advantages of providing baseload supply, which in turn impedes efficient market contracting for SPGs...
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...THE FUTURE OF TECHNOLOGY OTHER ECONOMIST BOOKS Guide to Analysing Companies Guide to Business Modelling Guide to Business Planning Guide to Economic Indicators Guide to the European Union Guide to Financial Markets Guide to Management Ideas Numbers Guide Style Guide Dictionary of Business Dictionary of Economics International Dictionary of Finance Brands and Branding Business Consulting Business Ethics Business Strategy China’s Stockmarket Globalisation Headhunters and How to Use Them Successful Mergers Wall Street Essential Director Essential Economics Essential Finance Essential Internet Essential Investment Essential Negotiation Pocket World in Figures THE FUTURE OF TECHNOLOGY THE ECONOMIST IN ASSOCIATION WITH PROFILE BOOKS LTD Published by Profile Books Ltd 3a Exmouth House, Pine Street, London ec1r 0jh Copyright © The Economist Newspaper Ltd 2005 All rights reserved. Without limiting the rights under copyright reserved above, no part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording or otherwise), without the prior written permission of both the copyright owner and the publisher of this book. The greatest care has been taken in compiling this book. However, no responsibility can be accepted by the publishers or compilers for the accuracy of the information presented. Where opinion is expressed it is that of the author and does not necessarily...
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