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Abstract--EPRI’s Smart Grid Demonstration Initiative is

focused on collaborating with electric utilities around the world and helping to advance the industry in regards to integrating Distributed Energy Resources (DER). An important aspect of these demonstration projects is the evolution of a smart distribution systems making integration of DER possible. A wide variety of factors play into every electric utilities strategy on deploying smart grid technologies including regulatory environment, age and functionality of existing assets, communication infrastructure, geography, reliability, cost to implement, and associated benefits. What appears to be a common technology implementation is actually very unique from one utility to the next and is therefore very important that the industry shares knowledge and lessons learned to help advance the industry. This paper provides several examples of integration approaches and early project results along with information on how to keep aware of the project status through 2014.

I. INTRODUCTION – BACKGROUND ON EPRI SMART GRID DEMONSTRATION INITIATIVE

chieving significant carbon emissions reductions in the U.S. electricity sector will involve contributions from a

portfolio of integrated solutions from efficiency to a broad range of Distributed Energy Resources (DER) including renewable generation, demand response, energy storage, and distributed generation. The widespread, efficient and cost-effective deployment of these technologies poses significant challenges beyond the development and enhancement of the technologies themselves including requiring end-to-end system integration in the distribution system as well as overall power system operations. Beyond the smart grid systems development and testing, customer engagement methods and technology play as a component of emissions reductions and grid efficiency [1].

To address these challenges, EPRI initiated a smart grid demonstration project in 2008 with several goals in mind including defining the role and business case of DER, requirements to integrate DER with system operations, and evaluate and advance standards development to facilitate widespread integration of DER. The main objective of the

The Smart Grid Demonstration Initiative is supported by The Electric

Power Research Institute and, as of February 2011, twenty electric utilities funding the research. The electric utility members include: American Electric Power, Ameren, CenterPoint Energy, Central Hudson Gas & Electric, Con Edison, Duke Energy, Entergy, Electricité de France, ESB Networks, Exelon (ComEd & PECO), FirstEnergy, Hydro-Québec, KCP&L, PNM Resources, Southern California Edison, Southern Company, Southwest Power Pool, Salt River Project, Tennessee Valley Authority, and Wisconsin Public Service.

demonstrations is to identify approaches for interoperability and integration that can be used on a system-wide scale to help standardize the use of DER as part of overall system operations and control. The project applies EPRI’s IntelliGrid® methodology to define requirements for the technologies themselves as well as the communication, information, and control infrastructures that support integration of the technologies. With the growth in smart grid demonstration activities in 2010, the initiative was extended to perform research through 2014 and is accepting new international utility members through 2011 to enable broader knowledge transfer from the collaborative research model.

II. DRIVERS OF SMART GRID DEMONSTRATION PROJECTS In mid-2010, EPRI initiated a smart grid survey to

understand key drivers of smart grid deployments. Although the number of survey responses was relatively small and not sufficient to draw firm conclusions, the responses did provide key trends from those electric utilities that did respond and the following information is taken from the report reporting the results of the survey [2].

At a high-level, survey respondents indicated the core drivers for Smart Grid deployments to be primarily economic and policy based. The economic drivers are similar to those that have existed over the last century – having the most effective way to match electric supply with demand 100% of the time and cover many subcategories.

The newest driver is the rate at which emerging technologies are advancing, such as, communications, computing power, energy storage, and renewable generation. These technologies are creating new opportunities and innovative ways to match electric supply and demand. In addition, there are emerging drivers to understand potential business models where power sales do not drive profits. In many deployments, the economic driver includes the opportunity to leverage economic stimulus funding. One of the key findings of the survey is that Smart Grid pilots and demonstrations are being pursued to determine costs and benefits so that the extension of the smart grid applications for wide-scale deployment can be pursued in an educated manner and help to understand the factors that can affect the costs and benefits.

In addition, a key external driver is regulatory policy goals including Green House Gas (GHG), Energy Efficiency (EE), Reliability, and Renewable Portfolio Standards (RPS). For example the European Unions (EU) 20-20-20 target. In March 2007, EU leaders endorsed an integrated approach to climate

Smart Distribution System Research in EPRI’s Smart Grid Demonstration Initiative

Matthew P. Wakefield, Program Manager, EPRI

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978-1-4577-1002-5/11/$26.00 ©2011 IEEE

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and energy policy to combat climate change and increase energy security while strengthening the EU’s competitiveness. To achieve these goals, a series of climate and energy targets to be met by 2020 are:

• A reduction in EU GHG emissions of at least 20% below 1990 levels

• 20% of EU energy consumption to come from renewable resources

• A 20% reduction in primary energy use compared with projected levels, to be achieved by improving EE

Similar GHG, EE, Reliability and RPS goals exist in the United States on a state-by-state basis as well as other countries around the world.

A majority of respondents indicated “Internal Operations” improvement as a key driver that prompted their Smart Grid project. The response to this and similar questions highlight the complexity of Smart Grid projects and that there is no one-size-fits-all in regards to what is the single most important driver for all utilities.

III. SMART DISTRIBUTION SYSTEM APPLICATIONS IN EPRI’S SMART GRID DEMONSTRATION INITIATIVE

In 2010, the Electric Utility Advisors of the Smart Grid Demonstration initiative reviewed eight approaches to integrate DER. The following section of this paper is a summary of the results of that effort [3].

The purpose of this effort was to discuss, compare and contrast different approaches to integrate DER that includes demand response, renewable generation, storage and distributed generation. Some of the use cases developed with the IntelliGrid methodology identified an Actor that is a Distributed Resource Availability and Control System (DRAACS).

The DRAACS maintains a reliable estimate of the amount of resources available for dispatch and is also responsible for accepting requests for blocks of energy and/or capacity and implementing that request by issuing load control requests utilizing an optimization function to determine the optimal resource and customer set. The DRAACS definition provides a good foundation to start the discussion on approaches to integrate DER, but can vary significantly from one project to the next even though there are many common architectural functions among the projects. Table 1 provides a summary of key Actors from eight projects that integrate DER.

Although there were many functional requirements, a relatively common theme of requirements emerged and can be broken down into four categories: • Distributed Intelligence • Visualization • Forecasting • Interoperability

Table 1. Key Actors from eight Projects Integrating DER

A. Distributed Intelligence One of the most common functions identified for systems

that integrate DER is the ability to process data and make decisions locally or have distributed intelligence and in some cases be autonomous. Distributed intelligence and localized decision making are being enabled by low-cost embedded computing capability that can reside near, or in some cases, directly in the resource itself. Because intelligence requirements at the “end-node” are less than the overall system intelligence, lower processing is required at those “end nodes.” Localized decisions can be made faster while still complying with centralized rules allowing for control decisions to be made at the right place and the right time. Generally speaking, failure modes in a distributed-intelligence architecture are less disruptive than in a centralized control architecture.

B. Visualization Visualization of DER was identified as a high priority

requirement. It is important to understand what resources are available and controllable to maximize both economic and reliability benefits. Some of the visualization capabilities include the ability to view not only aggregated resources, but also the ability to drill down to different levels from a substation, to a feeder and even down to the individual resource.

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C. Forecasting The ability to forecast and predict availability and

performance of resources was identified as a key function for many of the same reasons that visualization is important. The immaturity and low penetration of DER increases the uncertainty of the ability to predict their performance. This makes forecasting a challenge, but also reinforces our understanding of why it is important. Modeling and simulation efforts in many of the projects provide background knowledge to support forecasting algorithms. Micro-climate forecasting is an emerging technology that is growing in importance as we see increasing penetrations of renewable resources that are dependant on wind, cloud cover and other weather related factors.

D. Interoperability The ability to have interoperable systems is an industry

agreed upon requirement for smart grid applications and systems that integrate DER are no exception. A number of the related functions and capabilities of systems that integrate DER that are tied to interoperability were discussed by the electrical utility advisors. A strong focus on the use of standards and security was emphasized. Along with the importance of standards, several approaches identified the need to accommodate multiple communication media and technologies because no single communication technology is always the most cost effective to meet the diverse circumstances and needs of all the varying types of resources to be integrated.

Some integration approaches developed unique interfaces for each type of resource. For example, some systems had an architecture that had multiple interfaces depending on the type of resource, i.e. one type of interface for storage, another for PV, another for demand response, etc. A more common approach was to architect a system that was designed with an approach that characterized the physical capabilities of the resource. For example, characterizing the resource based on its physical capabilities, i.e kW, kWh, duration of availability of the resource. This approach simplifies the architecture and number of different interfaces that need to be developed.

1) Integration Challenges

One of the primary goals of the EPRI Smart Grid Demonstration Initiative is to advance the industry in regards to integration of DER. This is a known challenge and the efforts of the initiative are intended to understand the state of today’s integration capabilities, identify gaps, bridge the gaps in the host-site projects and support industry initiatives such as the NIST smart grid roadmap effort and identify areas for additional research.

Many of the integration issues relate directly to standards, lack of industry consensus, and maturity of new standards as well as cyber security. Because of the momentum in standards development, there is some uncertainty as to which standards will earn industry consensus so utilities are taking a careful approach to leverage standards that will meet their requirements, simplify integration and support long-term technology roadmaps. One of the presentations specifically

identified a challenge of finding available devices, software and support for some of the emerging standards.

An emerging opportunity associated with integrating AMI data with DMS and SCADA systems on the distribution system requires integration among systems that historically have been isolated. Smart meters on AMI systems have the capability to act as sensors to support distribution system applications beyond outage management in applications such as Conservation Voltage Reduction (CVR) and power quality monitoring. Another integration challenge was identified in the end-use equipment area. There are a wide variety of proprietary and standard protocols and a lack of industry consensus. The promise of existing standards such as BACnet and emerging standards such as Smart Energy Profile (SEP) 2.0 and OpenADR are planned for evaluation in several of the demonstration projects along with integrating legacy equipment. Related to the Customer Education challenge is a need to understand how to best leverage customer owned resources and how reliably they can be managed for both economic and reliable events.

IV. SUMMARY The collaborative model is a distinct aspect of EPRI

research, and applying this approach to multiple large-scale demonstration projects is proving to be a successful model to share information and advance the industry. While no single project can realistically test every technical scenario related to integrating DER, having multiple demonstration projects with common goals enables more research scenarios to be explored to advance DER integration interoperability. With EPRI providing research support across host-sites, a consistent and scientific approach helps to ensure results are extendable to all utility members, even for utility members who are not host-sites. The result is additional value from the sharing of research plans, lessons learned and gaps. Information regarding the initiative can be found on www.smartgrid.epri.com.

V. REFERENCES [1] M. Wakefield, "Smart Grid Demonstration Initiative," EPRI SPN

1016910, pp. 1, Aug. 2010. [Online]. Available: http://my.epri.com/portal/server.pt?Abstract_id=000000000001016910

[2] M. Wakefield, C. Haddad, A. Wright, "Smart Grid Leadership Report: Global Smart Grid Implementation Assessment.” EPRI, Palo Alto, CA: 2010. 1021417. Available: http://my.epri.com/portal/server.pt?Abstract_id=000000000001021417

[3] M. Wakefield, G. Horst, C. Haddad, “Architecture Considerations for Integration of Distributed Energy Resources (DER): EPRI Smart Grid Demonstration Meeting Panel Session Proceedings, March 4th, 2010,” EPRI, Palo Alto, CA: 2010. 1021265, Available: http://my.epri.com/portal/server.pt?Abstract_id=000000000001021265

VI. BIOGRAPHIES

Matthew P. Wakefield (Matt) is Program Manager at the Electric Power Research Institute (EPRI) managing EPRI’s international smart grid demonstration initiative. He has been a member of IEEE since 2009 and has over 23 years of energy industry experience and prior to joining EPRI, was the Manager of Applied Technology for Integrys Energy Group focused on developing and applying

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information and communication technologies related to real-time energy information transfer between control centers, generators, markets and consumers in both regulated and deregulated energy markets. He began his career in the United States Navy as a Nuclear Reactor Operator in the Submarine Fleet specializing in instrumentation and controls. He received his BS degree in Technology Management from the University of Maryland University College.