Smart Grids E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 516

Veröffentlichungsjahr: 2013

Beschreibung

On a worldwide basis, the development of SmartGrids is a consistent answer to the problem of an efficient and sustainable delivery of electric energy through distribution grids. SmartGrids are a combination of information and communication technologies and new energy technologies. There are many different definitions of the concept of SmartGrids and thus it appears indispensable to gather the knowledge available from both industry and research laboratories in one book. Distributed generation is rightly receiving an increased amount of attention and will become an integral part of urban energy systems, providing consumers and energy providers with safe, affordable, clean, reliable, flexible and readily-accessible energy services.
The aim of this book is to describe future electricity networks that will enable all energy services to become sustainable. The traditional design of network control systems with a centralized structure is not in-line with the paradigm of the unbundled electricity system and decentralized control; this is highlighted by looking at how future active networks will efficiently link small- and medium-scale power sources with consumer demands, allowing decisions to be made on how best to operate in real time. It also looks at the level of control required: power flow assessment, voltage control and protection require cost-competitive technologies and new communication systems with more sensors and actuators than presently used, certainly in relation to the distribution systems. To manage active networks, a vision of grid computing is created that assures universal access to computing resources. An intelligent grid infrastructure gives more flexibility concerning demand and supply, providing new instruments for optimal and cost-effective grid operation at the same time.

Leseprobe

Table of Contents

Foreword

Chapter 1. SmartGrids: Motivation, Stakes and Perspectives

1.1. Introduction

1.2. Information and communication technologies serving the electrical system

1.3. Integration of advanced technologies

1.4. The European energy perspective

1.5. Shift to electricity as an energy carrier (vector)

1.6. Main triggers of the development of SmartGrids

1.7. Definitions of SmartGrids

1.8. Objectives addressed by the SmartGrid concept

1.9. Socio-economic and environmental objectives

1.10. Stakeholders involved the implementation of the SmartGrid concept

1.11. Research and scientific aspects of the SmartGrid

1.12. Preparing the competences needed for the development of SmartGrids

1.13. Conclusion

1.14. Bibliography

Chapter 2. From the SmartGrid to the Smart Customer: the Paradigm Shift

2.1. Key trends

2.2. The evolution of the individual’s relationship to energy

2.3. The historical model of energy companies

2.4. SmartGrids from the customer’s point of view

2.5. What about possible business models?

2.6. Bibliography

Chapter 3. Transmission Grids: Stakeholders in SmartGrids

3.1. A changing energy context: the development of renewable energies

3.2. A changing energy context: new modes of consumption

3.3. New challenges

3.4. An evolving transmission grid

3.5. Conclusion

3.6. Bibliography

Chapter 4. SmartGrids and Energy Management Systems

4.1. Introduction

4.2. Managing distributed production resources: renewable energies

4.3. Demand response

4.4. Development of storage, microgrids and electric vehicles

4.5. Managing high voltage direct current connections

4.6. Grid reliability analysis

4.7. Smart asset management

4.8. Smart grid rollout: regulatory needs

4.9. Standards

4.10. System architecture items

4.11. Acknowledgements

4.12. Bibliography

Chapter 5. The Distribution System Operator at the Heart of the SmartGrid Revolution

5.1. Brief overview of some of the general elements of electrical distribution grids

5.2. The current changes: toward greater complexity

5.3. Smart grids enable the transition to carbon-free energy

5.4. The different constituents of SmartGrids

5.5. Smart Life

5.6. Smart Operation

5.7. Smart Metering

5.8. Smart Services

5.9. Smart local optimization

5.10. The distributor ERDF is at the heart of future SmartGrids

5.11. Bibliography

Chapter 6. Architecture, Planning and Reconfiguration of Distribution Grids

6.1. Introduction

6.2. The structure of distribution grids

6.3. Planning of the distribution grids

6.4. Reconfiguration for the reduction of power losses

6.5. Bibliography

Chapter 7. Energy Management and Decision-aiding Tools

7.1. Introduction

7.2. Voltage control

7.3. Protection schemes

7.4. Reconfiguration after a fault: results of the INTEGRAL project

7.5. Reliability

7.6. Bibliography

Chapter 8. Integration of Vehicles with Rechargeable Batteries into Distribution Networks

8.1. The revolution of individual electrical transport

8.2. Vehicles as “active loads”

8.3. Economic impacts

8.4. Environmental impacts

8.5. Technological challenges

8.6. Uncertainty factors

8.7. Conclusion

8.8. Bibliography

Chapter 9. How Information and Communication Technologies Will Shape SmartGrids

9.1. Introduction

9.2. Control decentralization

9.3. Interoperability and connectivity

9.4. From synchronism to asynchronism

9.5. Future Internet for SmartGrids

9.6. Conclusion

9.7. Bibliography

Chapter 10. Information Systems in the Metering and Management of the Grid

10.1. Introduction

10.2. The metering information system

10.3. Information system metering in the management of the grid

10.4. Conclusion: urbanization of the metering system

10.5. Bibliography

Chapter 11. Smart Meters and SmartGrids: an Economic Approach

11.1. “Demand response”: a consequence of opening the electricity industry and the rise in environmental concerns

11.2. Traditional regulation via pricing is no longer sufficient to avoid the risk of “failure” during peaks

11.3. Smart meters: a tool for withdrawal and market capacity

11.4. From smart meters to SmartGrids — the results

11.5. Bibliography

Chapter 12. The Regulation of SmartGrids

12.1. The regulation and funding of SmartGrids

12.2. Regulation and economic models

12.3. Evolution of the value chain

12.4. The emergence of a business model for smart grids

12.5. Regulation can assist in the emergence of SmartGrids

12.6. The business models are yet to be created

12.7. The standardization of SmartGrids

12.8. Conclusion

12.9. Bibliography

List of Authors

Index

First published 2012 in Great Britain and the United States by ISTE Ltd and John Wiley & Sons, Inc.

Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms and licenses issued by the CLA. Enquiries concerning reproduction outside these terms should be sent to the publishers at the undermentioned address:

ISTE Ltd27-37 St George’s RoadLondon SW19 4EUUK

John Wiley & Sons, Inc.111 River StreetHoboken, NJ 07030USA

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© ISTE Ltd 2012

The rights of Nouredine Hadjsaïd and Jean-Claude Sabonnadière to be identified as the author of this work have been asserted by them in accordance with the Copyright, Designs and Patents Act 1988.

Library of Congress Cataloging-in-Publication Data

Smart grids / edited by Nouredine Hadjsaïd, Jean-Claude Sabonnadière.

p. cm.

Includes bibliographical references and index.

ISBN 978-1-84821-261-9

1. Smart power grids. I. Hadjsaïd, Nouredine. II. Sabonnadière, Jean-Claude.

TK3105.S545 2012

333.793’2--dc23

2012006916

British Library Cataloguing-in-Publication Data

A CIP record for this book is available from the British Library

ISBN: 978-1-84821-261-9

Foreword

During the past century the energy supply to cities has changed dramatically. During the 19th Century, the major energy resource in cities was coal. Gas was used as a secondary energy source, produced from coal and distributed via a gas network, with one of the major applications being lighting which was a competitor for oil.

At the turn of the 20th Century, electricity was deployed as a secondary energy source. Again, lighting was a major field of competition, where automation and user friendliness were seen as the major advantages of electricity. In order to smooth out demand, other applications were promoted (drives, household equipment, etc.). Small, local grids were interconnected in order to further smooth demand and improve reliability while limiting reserves. This has led to the system as it is known today. Within the cities, radially operated electricity grids are installed at a low voltage, typically three-phase 230/400 V in continental Europe. At nodes, this grid is linked by a transformer to a medium voltage supply (in the order of 10 kV). The medium voltage grid is often designed as a meshed grid, but operated in a non-meshed situation. The electric energy is brought to the city by high voltage substations that are supplied by the meshed — thus redundant — transmission grid, offering international links.

In many cities, the gas network is transformed into a distribution grid for natural gas for heating purposes. Some countries have opted for heat networks instead.

Both the liberalization of the electricity and gas market and the drive towards an environmentally sustainable energy supply, incorporating the reduction of greenhouse gas emissions and the increased use of renewable energy resources and flow, are stimulating the interest of different stakeholders in the energy field. In the coming years, energy demand will become increasingly tailored to customer needs. Users are not really interested in energy as such, but in so-called energy services: lighting, transport, heating/cooling, information and communication technologies (ICTs), home appliances, etc. In addition to quality of service and cost reduction, total connectivity, energy “on demand”, service-oriented portfolio and flexible contract management will also play a leading role in fulfilling customer expectations.

The aim of this book is to describe the future electricity networks that will enable all energy services to become sustainable. Several chapters deal with the elements of the electricity system. Attention is not only given to the power elements of the transmission and distribution grid, but also to new types of demand, and especially to all aspects of control and system interactions.

The grid is defined as the system covering all wires and equipment that play a role in supplying consumers and providing access to generation technologies. Distributed generation will receive increasing attention over time and will become an integral part of cities’ energy systems, providing consumers and energy providers with safe, affordable, clean, reliable, flexible and readily-accessible energy services. Promoting and deploying distributed generation technologies should benefit energy consumers, the European energy system and the environment through the optimization of the value chain from energy suppliers to smart and large numbers of end users using SmartGrid infrastructure.

The SmartGrid developments aim to produce a set of “plug and play” interfacing modules using standardization and modularization, resulting in lower generation costs, material use, etc. This will lead to lower costs throughout the power delivery chain, given the stringent environmental framework and the market approach of the energy system. These plug and play interfacing modules are environmentally friendly (e.g. easy to recycle/reuse) and have very few to no unwanted effects on members of the public (they are not toxic, there is no interference, and they produce acceptable levels of EMF, etc.). The modules can, to a high degree, be customized to individual needs. Through standardization, modularization and programmable functionality, an economy of scales is possible leading to cheaper production, lower inventory costs and easily expandable and maintainable systems for the user. This can give Europe a competitive edge in the world market. This can offer the customer choice and quality of supply at relatively low cost, provided that minimal technical requirements are met and that these are measurable enabling network operators to maximize efficiency, flexibility and reliability through the use of advanced smart technology.

The variability of renewable generation, such as wind and photovoltaics, can have considerable effects on power system operation, mainly on security margins and consequently operational costs. This clearly requires integrated control of both central and distributed generation at all voltage levels. Given the necessary technological advancements and financial incentives, current operating practices based on centralized control need to move towards a decentralized approach. Technological developments in the ICT area (telecommunications, distributed control, advanced forecasting techniques, on-line security assessment, etc.) can contribute significantly to these developments. The grid interfaces to be developed have to include these elements in agreement with the results from the customer integration and effective demand-side management viewpoint. Possible synergies of distribution management systems and the impact of storage in power networks studies (peak load, power quality and penetration of renewables) need to be analyzed.

In general, simulation tools and methods for the analysis of distribution systems were historically developed and used in an off-line environment to study aspects of operation and development. Such tools have sometimes been upgraded and customized for use in an on-line environment for the purpose of generation dispatching, system state estimation and security analysis. The simulation and analysis software is orientated to conventional generation by centralized plants and unidirectional power flow.

A large number of micro-generators, uncertainties in distributed generation output (due to intermittent availability of renewable energy sources (RES) or dependence of distributed generation operation on other services such as heat demand driven combined heat and power (CHP)) and changes in power flows, especially at the distribution networks, are issues that cannot be effectively dealt with by methods and simulation tools that are widely applied. Moreover, distributed generators are often connected to networks through power electronics interfaces. New, advanced controllers based on power electronics and various types of storage devices are developed for distributed frequency and voltage control. These aim to support the network. There are limitations in the simulation of the commutation process in power electronic converters and in advanced digital control. Finally, aspects of data exchange and the communications requirements of network operation are largely ignored by the models.

Distributed network operators (DNO) need new methods and appropriate computing tools to correctly study the aspects of distributed generation network integration in order to anticipate technical problems and barriers, identify solutions, and underpin decisions on new investments. The novelty of the new problems requires the development of new mathematical approaches. Research must cover a range of topics relevant to the simulation and analysis needs for operation and the development of future electric networks. They should be confirmed through a discussion with the key stakeholders. The role of each actor and the relations required between the different actors need to be made clear. Questions — such as what is the role of the manufacturer? What type of data/information needs to be exchanged between the manufacturer and DNO? And what data need to be transmitted on-line for power network control and how? — need to be addressed.

There are several levels of decentralization of the network control that can be applied, ranging from a fully decentralized approach to hierarchical control. By using this distributed control strategy, the lower level of control can be independently operated and disconnected from the higher control hierarchy in order to form an islanded operation that has the ability to balance supply and demand locally with an acceptable power quality determined by local system requirements. Such control-independency enables parts of the network to be operated in two operation modes: autonomous (islanding) or grid-connected. This possibility increases the reliability of supply within the parts of the network penetrated by distributed generation, since their internal electricity resources can be used to supply their own demand during disruption in the public grid. On the other hand, in normal situations when the grid-connected mode is applied, the system resources — including the micro-sources — can be used and shared to supply system demand in order to achieve the maximum system economic efficiency.

The future active network will efficiently link small- and medium-scale power sources with consumer demands, allowing decisions to be made on how best to operate in real time. The level of control required for this is significantly higher than found in the present transmission and distribution systems. Power flow assessment, voltage control and protection require cost-competitive technologies and new communication systems with more sensors and actuators than presently used, certainly in the distribution systems. To manage active networks a vision of grid computing is created that assures universal access to computing resources. An intelligent grid infrastructure gives more flexibility concerning demand and supply, providing new instruments for optimal and cost-effective grid operation at the same time. Intelligent infrastructure enables the sharing of grid and information technology resources including ancillary services, balancing, microgrids behaving as virtual power plants, etc. It creates a framework for all grid users including the transmission system operators and DNOs.

In order to exploit the advantages of distributed generation (including RES) it is necessary to follow a “system approach”: distributed generation will not feed the network in a stand-alone mode, but will be fully integrated into the network. As is already the case for the high voltage network, the medium and low voltage networks will in turn become “active”. The energy generated by distributed generation will be dispatched accordingly and the distributed generators will have to provide ancillary services to the network and will become normal market participants.

Much of the equipment on the current electricity networks was installed with a design life of about 40 years, allowing for the anticipated increase in load over that period. An increasing proportion of the material is reaching the end of its design life. Meanwhile, the nature of the loads on the networks has changed beyond that predicted when planned and designed. The demand has doubled since the 1960s; peak demand and its timing are also changing and will continue to do so, in less than certain directions.

As very significant investments will be required to simply renew this infrastructure, the most efficient way forward is to incorporate innovative technologies and solutions when planning and executing this renewal. The approach to “design-in” greater network capability and functionality will also allow for the management of uncertainties and future, as yet unforeseen, changes.

Asset management is traditionally hindered by the old paradigms of reliability and the long pay-back periods (> 30 years) for the capital-intensive plants and grid equipment. The underlying uncertainty associated with recovery of long-term investments calls for an improved “knowledge” of the natural lifecycles of networks and their existing components. Any consideration of future electricity networks will also take into account the life-expectancies of future installed/refurbished assets — and the functional performance expectations (e.g. reliability, security, availability, accessibility, flexibility, adaptability, safety, environmental impact, aesthetic impact, operational impact, efficiency and whole-life cost) of all stakeholders with respect to those assets from installation to disposal.

The traditional design of network control systems with a centralized structure is not in line with the paradigm of the unbundled electricity system and decentralized control. In the unbundled and competitive environment, systems often work closer to their limits, and hence all system resources and services should be managed precisely to ensure a high level of reliability. The main goal from the viewpoint of defense and restoration is a “self-healing” network with a high level decentralized preventive control and outage management with automated network restoration. A main goal and objective should therefore be to achieve scalable, flexible supervisory control and data acquisition (SCADA) systems for network operations (SCADA for low voltage at the DSO level and customized automation applications).

As the chairman of the FP7 Technology Platform on SmartGrids, I warmly welcome the book that you have in hand. It is a concise contribution to the field and is brought to you by a number of well-known contributors that have carried out high-level research on different aspects of the future grid. I trust it will prove to be a major resource for the scientific and technical community.

Professor Ronnie BELMANSChairman Technology Platform on SmartGridsEuropean UnionMarch 2012

Chapter 1

SmartGrids: Motivation, Stakes and Perspectives1

1.1. Introduction

Power systems, after several decades of slow development, are experiencing tremendous changes due to several factors, such as the need for large-scale integration of renewable energies, aging assets, energy efficiency needs and increasing concerns about system vulnerability in the context of the multiplication of actors in free energy markets The complexity of operations is increasing, which will ultimately require the introduction of more intelligence in the grid for the sake of security, economy and efficiency, thus allowing the emergence of the SmartGrid concept.

1.1.1. The new energy paradigm

The current operation of electrical networks is based on four levels resulting from the structure of the global electrical system:

Power generation: most power is generated by large units installed in strategic locations for operation with respect to the power grid.

The transmission system, which allows power to be transferred from large power plants to large consumption centers and other sub-transmission and distribution systems. This is the backbone of the whole power system, which contains sophisticated equipment and has highly centralized management.

Distribution grids: these are at the interface between the transmission grid and the end user (the customer). They are connected to the transmission grid through interface buses called substations via transformers and, for economic reasons and simplicity of operation, are generally operated in radial structures. They are thus characterized, in the absence of significant local generation sources (interconnected at the distribution level), by unidirectional energy flows (energy traditionally always flows in the same direction, from the substation to the end user).

End users are mostly passive customers characterized by non-controllable loads and do not contribute to system management.

The first three levels, although institutionally unbundled in a deregulated environment with responsibility domains clearly defined, are closely interdependent and are governed by specific physical laws, related in particular to the generationconsumption balance or to respecting technical constraints. This system as a whole was designed with the objective of generating, transmitting and distributing electrical energy under the best conditions of quality and economy. Regarded as the most complex system ever built by man, it is made up of millions of kilometers of lines and cables, generators, transformers, connection points, etc. It also integrates several voltage levels, sophisticated protection and control equipment and centers.