A White Book on

Smart Grid

Faculty of Information Technology, Mathematics and

Electrical Engineering

Draft Version – 2011

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Revision History Date Version Author Department

Sep 2011 Draft Mohsen Anvaari IDI Sep 2011 Draft Tosin Daniel Oyetoyan IDI

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Table of Contents

1. Introduction ............................................................................................................................ 4  

2. Definition of Smart Grid ........................................................................................................ 5  

3. Smart Grid Structure .............................................................................................................. 6  

4. Smart Grid Characteristics, Functionalities and Services ...................................................... 7  

5. Quality Attributes in Smart Grid ............................................................................................ 9  

6. Challenges and Research Directions in Smart Grid ............................................................. 10  

7. NTNU Smart Grid Project ................................................................................................... 11  

7.1. Research Projects .......................................................................................................... 11  

7.2. Positions ........................................................................................................................ 13  

7.3. Courses involving Smart Grid ....................................................................................... 13  

7.4. Smart Grid Participants ................................................................................................. 14  

8. References ............................................................................................................................ 15  

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1. Introduction

The increasing demands for energy, the need for carbon footprint reduction and the push for more energy management are driving governments, utilities and consumers to seek for a smarter way of managing the current electricity grid [7, 8]. The result is the introduction of Smart Grid as the evolutionary approach that can bring the ‘smartness’ to the traditional power grid in order to achieve the mentioned objectives. Different countries have commenced several projects to implement the Smart Grid. Main aspects have been the injection of new and green energy resources into the grid (such as wind, solar and biomass), introduction of Plug-In Hybrid Electric Vehicle (PHEV) and development of several software and automation systems including communication infrastructures that will allow efficient and bi-directional customers’ participations in the system. The benefits of such evolution would be a reliable, secure, efficient, economic, environmental friendly and safe electricity grid.

NTNU has initiated a multidisciplinary research project in Smart Grid to study the current state of power grid in Norway and develop new approaches to make the grid smarter. This white book summarizes some facts about Smart Grid and also introduces the Smart Grid project in NTNU. The remainder of the document is organized as follows: Section two introduces the Smart Grid concept, section three presents the structure of Smart Grid, in section four the functionalities and services of Smart Grid are discussed, section five presents the quality attributes in Smart Grid, section six discusses the research challenges in Smart Grid, and section seven introduces the Smart Grid project in NTNU.

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2. Definition of Smart Grid

There are several definitions for Smart Grid from different organizations such as European Technology Platform on Smart Grid (SmartGrids ETP), International Electrotechnical Commission (IEC), US Department of Energy (DOE), etc. DNV in Norway has a definition inspired by IEC and SmartGrids ETP: “A Smart Grid is an electric power network that utilizes two-way communication and control-technologies to cost efficiently integrate the behavior and actions of all users connected to it – in order to ensure an economically efficient and sustainable power system with low losses and high levels of quality, security of supply and safety”[1]. Smart Grid is enhanced version of today’s electricity grids and as a result doesn’t look significantly different from what we have today that is made from copper and iron lines or cables [1]. What it actually does is adding intelligence to the traditional power grid in an evolutionary process. Figure 1. shows this evolution.

Figure 1. Evolutionary process of smartening the electricity grid[2]

There are some misconceptions for Smart Grid as well. The main one is considering smart meters as Smart Grid. Even though smart metering enables some features and functionalities of Smart Grid, Smart Grid encompass a much wider area of technologies and solutions and is by no means restricted or strictly delimited by the introduction of smart metering [3]. The other mistake is considering Smart Grid as a revolution in power electricity grids. As mentioned earlier, Smart Grid will be an evolution [1].

In the following section the structure of Smart Grid will be discussed to see what are its domains, which components are included in the domains and how they are connected.

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3. Smart Grid Structure

Like other systems Smart Grid as a structure includes constituent components and their relationship. Since there is not a worldwide-defined structure for Smart Grid yet, different authors and organizations have considered different structures for it. Even though, the difference is in their different point of view, otherwise a common structure can be found among them. IEEE has defined a layered architecture for Smart Grid that divides the Smart Grid into three foundational layers: Information Technology Layer, Communication Layer, Power and Energy System Layer [4]. Shargal and Houseman have the same idea. In their conceptual architecture Grid Hardware corresponds to Power and Energy System Layer and Communication Backbone can be considered as Communication Layer. The correspondent layer for Information Technology is divided into three other layers in their model: Data Standards, Data Management and Knowledge Continuum [5]. SmartGrids ETP considers a similar architecture for any active distributed network: copper based energy infrastructure, communication layer and software layer [6].

Besides the mentioned layered architecture, NIST considers seven domains for Smart Grid: Bulk Generation, Transmission, Distribution, Operations, Service Providers, Markets and Customers [7]. For each domain the aforementioned three layers can be applied. As a result Figure 2. shows the domains and layers of Smart Grid and the included components. It is actually a mixture of Smart Grid architecture from IEEE and Smart Grid domains from NIST.

Figure 2. Smart Grid Structure

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4. Smart Grid Characteristics, Functionalities and Services

The Smart Grid as defined [7] incorporates the electricity grid and communication technologies. It is envisioned to provide modern electrical services that transcends from Generation domain to the consumer end. The Smart Grid characteristics and functionalities can thus be summed up as follows [7, 8, 15]:

1) Integration of all generation and storage options: The Smart Grid will incorporate several smaller distributed and renewable sources of energy such as wind, solar, biomass etc. and traditional large central power plants.

2) Enabling active participation by consumers: With dynamic energy information available to consumers, it becomes possible for consumers to engage in several control options of their household equipments, respond to demand by adjusting their energy usage and engage in electricity markets.

3) Enabling new products, services and markets: Examples include linking of energy buyers to sellers, brokers, integrators and aggregator services and also Plug-In Hybrid Electric Vehicles (PHEV) and Vehicle to Grid services.

4) Provision of power quality for the digital economy: Because of monitoring and diagnosis capabilities the Smart Grid will be able to respond to power quality issues. It will be possible also to supply various grades of power quality at corresponding pricing levels.

5) Optimization of asset utilization: The Smart Grid will give knowledge about what is needed, allow more power through existing assets and lead to improved maintenance processes.

6) Anticipating and responding to system disturbances: The Smart Grid will be able to perform continuous self assessment, it will detect, analyze, respond to and restore grid components and network sections.

7) Operating resiliently against attack and natural disasters: The Smart Grid will be able to provide system wide solution to both physical and cyber security.

Figure 3 Smart Grid key functions [15]

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Thus, the Smart Grid components and their services equally can be categorized as represented in Table I [7, 13].

Table I: Smart Grid components and services

Smart Grid Components Services

Advanced Metering Infrastructure Interval measurement, load control, pre-payment, tariff flexibility, communication and data security.

Supervisory Control And Data Acquisition (SCADA)

Automated control of transmission and distribution, Substation automation,

Demand Response Load adjustment, dynamic pricing

Plug-In Hybrid Vehicle (PHEV) Alternative energy source for vehicles, Peak load leveling (Valley filling and Peak shaving)

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5. Quality Attributes in Smart Grid

The Smart Grid quality attributes cut across the hardware, firmware and software at the various Smart Grid domains (Generation, Transmission, Distribution and Consumption). Here, few examples are given to explain this topic.

The two-way communication paradigm in Smart Grid allows the customer to actively participate in the Smart Grid market via the Internet thereby exposing the system to cyber attacks. Thus, there is significant focus on the cyber security property in the Smart Grid [7]. There is a need also for the Smart Grid system to fulfill the CIA (Confidentiality, Integrity and Availability) security criteria [14]. It is therefore imperative to analyze the vulnerabilities and make risk assessments at each Smart Grid components and layers in order to evolve a secured system [13, 14]. For example: confidentiality or privacy of data is an important quality or security feature for the Smart Grid household unit. A compromised meter data could lead to theft, revelation about who is using what, when it is being used and where it is being used.

As a System of System (SoS) [7, 9, 10], many potential sources of Software quality consideration can be exploited. These sources can be explained by the associated risk in such Smart Grid system. These include [9]:

a) Potential for change in the system(s) from any direction (that is, from stakeholders or constituent system as well as from evolving business requirements).

b) Less predictability regarding stakeholders needs, technology advances and component behaviour which is typical in an environment with no central control.

c) Failures with causes or impact beyond the individual system boundary. An example is the August 14, 2003 blackout in the US [11].

d) Constrains in terms of new development and evolution because of existing collection of design choices.

e) Limited knowledge of individual system state and behaviour.

The above risks can strongly compromise the safety, reliability and availability of the system. Thus, we can summarize the Smart Grid quality attributes to be based on its safety, reliability, availability, integrity and confidentiality.

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6. Challenges and Research Directions in Smart Grid

The growing Smart Grid behind today’s electricity supply introduces many challenges and opportunities for research. Based on the Smart Grid functions, we discuss below some areas of research in Smart Grid presented in [15].

Renewable Energy Integration: This is an important research area in the Smart Grid. Below are few of the research topics within this context.

(1) Wind forecast. The challenge in this topic is that the generation profile has to be predicted over a period of time. To achieve this, the wind speed and direction need to be accurately predicted, however, the wind is intermittent in nature and thus it is not easy to have such an accurate prediction on a long term.

(2) Wind generation dispatch (3) Power flow optimization (4) Power system stability

Self- Healing and Cyber Security: This means that the grid has the ability to respond to failure and take action. To achieve this, automation and communication infrastructures have to be put in place. These components introduce security and reliability challenges. Security challenges because automated equipments and systems are connected to the communication network thereby exposing the grid to cyber attacks.

Energy Storage System: It is important to be able to store renewable energy; however, there are challenges that need to be addressed to make this available. Some of these are:

1) Cost: Energy storage systems are very expensive. Further research is needed to develop cost efficient storage systems.

2) Complexity: Integrating new storage systems introduce additional and complex analysis of the power systems.

3) Non-flexibility: There is need for research on how to make the storage technology more flexible and adaptable to various systems.

Software Management: The Smart Grid software is diverse and distributed in nature running at different nodes of a highly heterogeneous system. How then can these software be better evolved and managed in a way that guarantee a consistent and safe system? More research is needed in this topic.

In addition, other important area of research in Smart Grid includes power quality, consumer motivation and reliability.

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7. NTNU Smart Grid Project

As an important contributor to renewable energy sources, a Norwegian national center for Smart Grid is under development. The initiative includes participation from universities, research organizations as well as a significant involvement from industry. The initiative covers disciplines as electrical engineering, computer science, telecommunication, telematics, cybernetics, end-user participation, business models and well as societal aspects. A national Smart Grid laboratory is also under development together with demonstration projects. Smart Grid will be an important research topic in the coming years and currently eleven positions are vacant.

7.1. Research Projects

The NTNU research initiatives are published in the various projects that address the Smart Grid challenges. These research projects are as follows:

Operation and control

The overall aim of the project is the development of advanced monitoring and control solutions to ensure security and reliability in operation of interconnected power transmission systems. Three PhD fellowships are available.

Potential instability

System stability is the most important pre-requisite when designing electrical grids integrated with a large number of switching converters. Due to their non-linear and time varying characteristics, modelling and stability analysis of such systems are complex and cumbersome. After a thorough investigation of the state of the theoretical art on modelling and stability, this research will be focused on the development of a stability analysis tool that can accurately capture the potential phenomena linked to the interaction between converter-embedded control algorithm and the characteristics of the electrical grid.

Critical infrastructure

The aim of the project is to model and analyze the vulnerability and dependability of the system of systems (ICT, power grid, power consumption and generation) through a holistic view of the smart grid as a critical infrastructure. The work should encompass issues such as overall system structure; interaction of systems; dependability, information security, dependability and performance of distributed management system; and information security and dependability related to metering, remote control and monitoring.

Reliability of wind energy

The present project is concerned with reliability modeling and reliability assessment for wind turbines and wind farms and their role in the Smart Grid technology. Given the complex structure of wind turbines, and the additional fact that their performance is strongly related to the

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environment where they are installed, it is clear that the modeling and analysis will require both system knowledge and appropriate field data, as well as statistical methodology of several kinds

Integrated Communication and Control

The overall aim of the project is to study integrated design of control and communication systems for reliable closed-loop control over wired and wireless networks. Two PhD fellowships are available

Improved Management of software

One of the main challenges Smart Grid will have is the management of various software that drive these new systems at different domains (generation, transmission, distribution and consumption) and nodes of the Smart Grid network. The actual software is developed and run by a large number of companies in many countries. Such software is in a never-ending state of flux because of changing expectations from the direct and indirect users of software-driven artifacts. When, how and by whom should then a piece of software be evolved, e.g. with use of Open Source Software of undocumented quality? A perennial problem is to have updated dependencies between the different software parts, possibly distributed and versioned.

Parallelization of computations

The purpose of this project is to contribute to the state-of-the-art within this research field and with test cases and applications from the SmartGrid area. The project will study existing methods, techniques and tools for optimizing the energy efficiency of multicore computations and also explore new ones. Modern approaches such as design space exploration, system level simulations, autotuning and use of performance & energy counters are relevant.

Next Generation Control Centers for Smart Grid

The project is based on the general expectation that the deployment of Smart Meters and new sensors will drastically increase the data volume to be managed by Distribution and Transmission System Operators.The project’s main goal is to see how the increasing amount of real time and static data can be utilized most efficiently in order to operate the power system in a safer, more reliable and cost effective way. IDI is responsible for WP 4 that will provide decision support to the control room. Operators in the control room monitor a large amount of data today and the amount of data will most possibly increase in a future smart grid. Overload of data and information will create a problem that needs to be addressed. WP 4 aims to develop a smart system that analyses the real time data stream, detects the indications of anomalous events, and suggest preventive or repair actions. Since many of such events/situations may be re-occurring, the network should remember past similar situations (and how they were solved) to use them in handling new problems. Hence, decision-making mechanisms that use experience-based reasoning will constitute a main focus in this WP. Two subtasks involved in this work

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are (i) data abstraction and (ii) experience-based decision methods where the outputs of the former are a set of indicators that can be used as input to the latter subtask.

7.2. Positions

• IME faculty has opened 11 PhD positions within smart grid area. • One Professor positions in Dept. of power systems. • Plus the Phd/Postdoc positions opened for the 3 projects funded by NFR, industry and

IME

7.3. Courses involving Smart Grid

• The course “Experter i Team” have 6 student groups with SmartGrid focus in spring 2011. Presentations from these groups can be found here.

• In the course “ElektriskeKretser” (taught by Frank Mauseth), a chapter titteled “Smart Grid” has been introduced in the lecture notes of the course.

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7.4. Smart Grid Participants

Faculty Department Name

IME data teknikk og informasjons vitenskap

Pinar Öztuürk Boye Annfelt Hoverstad Axel Tidemann Helge Langset ReidarConradi Tosin Daneil Oyetoyan Mohsen Anvaari Lasse Natvig Abdullah Al Hasib

elektronikk og telekommunikasjon

Kimmo Kansanen Reza Parseh

elkraft teknikk Kjell Sand Fredrik Christensen Kjetil Uhlen Marta Maria Cabrera Molinas

teknisk kybernetikk Morten Hovd Tor Arne Johansen

telematikk Poul E. Heegaard Finn ArveAagesen

SVT industriell økonomi og teknologiledelse

AsgeirTomasgard ØysteinMoen

Institutt for sosiologiogstatsvitenskap

MaritReitan

HF tverrfagligekulturstudier Marianne Ryghaug William Throndsen

NT institutt for materialteknologi Hans JørgenRoven IVT program for

industrielløkologi Edgar Hertwich Raquel Santos Jorge

Rektorsstab prorektor Jan Onarheim Per Arne Wilson

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8. References [1] Langeland, T. and Greiner, C.,The Smart Grid – What It Is and What It Is Not, FremtidenErElektrisk, NEF

TekniskMøte, Trondheim, March 2011.

[2] Technology Roadmaps: Smart Grids, International Energy Agency, April 2011.

[3] Position Paper on Smart Grids – An ERGEG Public Consultation Paper, European Regulators Group for

Electricity & Gas, December 2009.

[4] IEEE P2030 Draft Guide for Smart Grid Interoperability of Energy Technology and Information Technology

Operation with the Electric Power System (EPS), and End-Use Applications and Loads, IEEE Standards

Association, 2011.

[5] Shargal, M. and Houseman, D., The Big Picture of Your Coming Smart Grid, Smart Grid News, March 5, 2009,

Available at:

[6] http://www.smartgridnews.com/artman/publish/commentary/The_Big_Picture_of_Your_Coming_Smart_Grid-

529.html, Last visited date: May 19, 2011.

[7] SmartGrids – Strategic Deployment Document for Europe’s Electricity Network of the Future, European

Technology Platform, April 2010.[7] NIST Framework and Roadmap for Smart Grid Interoperability

Standards, Release 1.0, Office of the National Coordinator for Smart Grid Interoperability, U.S Department of

Commerce, January 2010.

[8] Joe Miller. “Understanding the Smart Grid: Features, Benefits and Costs.” Illinois Smart Grid Initiative. July 8,

2008.

[9] Rita Creel and Bob Ellison.“System-of-Systems Influences on Acquisition Strategy Development.” Carnegie

Mellon University. 2008.

[10] John Fallows. “A System of Systems. Emerging Ideas.”Sierra Systems Management Consulting. May 10, 2010.

[11] NORTH AMERICAN ELECTRIC RELIABILITY COUNCIL. “Technical Analysis of the August 14, 2003,

Blackout:What Happened, Why, and What Did We Learn?” 13 July 2004.

[12] IME, NTNU. “The Smart Grid Research Initiatives.” http://ime.ntnu.edu/research/smartgrid.

[13] Parminda Karlon. “Security Issues in System Development Life Cycle of Smart Grid.” Master Thesis, Califonia

State University. 2011.

[14] NIST. “Information Security.” In NIST Special Publication 800-53 Revision 3. August 2009.

[15] F. Bagnan Beidou, Walid G. Morsi, C.P. Diduch and L. Chang. “Smart Grid: Challenges, Research Directions

and Possible Solutions”2nd IEEE International Symposium on Power Electronics for Distributed Generation

Systems (PEDG), 2010.