The Smart GridEnabling Energy Efficiency and

Demand Response

Clark W. Gellings

Brevard Community College

ETP1400 Distributed Electrical Power Generation and Storage

Bruce Hesher

433-5779

Chapter 6: The IntelliGridSM architecture for the Smart Grid

The challenge before the energy industry remain formidable. The 2003 blackout in the northeast reminds us that electricity is indeed essential to our well-being. It highlighted the most fundamental of electric functions: getting power from where it is made to where it is used.

After many years with little advancement, a number of factors are now driving modernization of the distribution grid:

• the digital age and its power quality requirements.• saturation of the current grids capacity.• emerging competitive power markets.• distributed generation.

Today’s electricity infrastructure is inadequate to meet rising consumer needs and expectations.

Introduction p113

America’s power distribution grid is being stressed in new ways that it was not designed for. EPRI has identified a number of improvements to the system that should reduce the threat and severity of power outages.

Reactive power reserves in the region: Additional power required to maintain voltage when loads such as motors and air conditioners come online.

Power flow patterns over the entire region: Regional coordination, communications, and control are needed.

New power flows resulting from changing geographic patterns of consumer demand and the installation of new power plants.

Launching the IntelliGridSM

In 2001, EPRI and the Electricity Innovation Institute (E2I) initiated a program called the Consortium for Electric Infrastructure to Support a Digital Society (CEIDS). CEIDS played a major role in the development of the Smart Grid concept. CEIDS later morphed into the IntelliGridSM and E2I was absorbed by EPRI.

Vision: to develop the science and technology that will ensure an adequate supply of high-quality, reliable electricity to meet the energy needs of the digital society.

Mission: CEIDS provides the science and technology that will power a digital economy and integrate energy users and markets through a unique collaboration of public, private and governmental stakeholders.

The IntelliGridSM Today p116

The IntelliGridSM is addressing five functionalities in the power system of today:

Visualizing the Power System in Real Time.

Increasing System Capacity.

Relieving Bottlenecks.

Enabling a self-healing Grid.

Enabling (Enhanced) Connectivity to consumers.

Visualizing the Power System in real Time

This attribute would deploy advanced sensors more broadly throughout the system on all critical components. The sensor will be integrated with real time communications and computational ability so controls (manual or automated) can respond to changing circumstances.

Increasing System Capacity

Effort to increase capacity particularly in high voltage systems. Entails building more transmission circuits, bringing substations up to NERC N-1 criteria, making improvements on data infrastructure, upgrading control centers, and updating protection schemes and relays.

Relieving Bottlenecks

Eliminate bottlenecks preventing truly functional wholesale market and to assure system stability. Increases power flow, enhanced voltage support, and allowing the operation of the electric system on a dynamic basis.

Enabling a Self-Healing Grid (SHG)

Once the above goals are put in place, it is possible to consider controlling the system in real time. Will require widespread deployment of power electronic devices such as power electronic circuit breakers, and flexible AC transmission technologies. By integrating power electronics (SCR’s, TRIACS, and other thyristors) with a control architecture (sensing devices and intelligence) the grid can become self-healing.

Thyristors Thyristors are power semiconductor devices that control a large current via a digital logic gate pin. The TRIAC dimmer was shown earlier. The Silicon Controlled Rectifier (SCR) functions as a high power diode (one-way current valve) with an on switch. Once turned on the SCR will conduct until the current drops too low. The TRIAC’s gate pin is a voltage controlled on and off switch. The TRIAC will conduct in either direction as long as there is voltage on the gate.

Enabling (Enhanced) Connectivity to Consumers

Once a communications system is present, connectivity to the consumer can be enhanced with communications. Three new areas of functionality will be possible:

• Electricity services (e.g. added billing information of real-time pricing)

• Service related to electricity: home security and appliance monitoring.

• communications services (data).

The IntelliGridSM architecture contains a concept called EnergyPortSM. It is a consumer gateway allowing price signals, decisions, communications, and network intelligence to flow back and forth. It can facilitate:

• Pricing and billing processes that would support real time pricing.

• Value-added services such as billing inquiries, service calls, outage and emergency services, power quality monitoring, and outage diagnostics.

• Improved building and appliance standards.

Consumer energy managements through sophisticated on-site energy managements systems.

Easy “plug and play” connection of distributed energy resources.

• Improved real-time system operations including dispatch, demand response, and loss identification.

• Improved short-term load forecasting.

• Improved long-term planning.

A Smart Grid Vision Based on the IntelliGridSM Architecture

The IntelliGridSM will enable achievement of the following goals:

• Physical and information assets that are protected from man-made and natural threats and a power delivery system that can be quickly restored.

• Extremely high delivery of high-quality “digital grade” power.

• Availability of a wide range of always-on, price-smart, consumer and business services.

• Minimized environmental and societal impact by improving use of the existing infrastructure; and the use of energy efficient equipment and services.

Barriers to Achieving the Vision p119

To achieve this vision of power delivery system the following barriers and vulnerabilities need to be overcome:

The existing grid is vulnerable to human error, natural disasters, and intentional physical or cyber attack.

Investment in expansion maintenance of the infrastructure is lagging, while electricity demand is growing.

The existing power delivery system is not being expanded to facilitate wholesale competition in the power industry and does not facilitate connectivity between consumers and markets.

The current grid infrastructure cannot support levels of power, security, quality, reliability, and availability needed for economic prosperity.

The infrastructure does not adequately accommodate emerging technology including distribute energy resources and energy storage nor does it facilitate business opportunities for retail electricity/information services.

The present power delivery systems was not designed to meet the needs of a digital society.

Communication Architecture: The Foundation of the IntelliGridSM p119

A standard communications architecture must be developed and overlaid on today's power grid. This “Integrated Energy and Communications System Architecture” (IECSA) will be an open standards architecture for a data communications and distributed computing infrastructure.

The IntelliGridsm Architecture is free and open to anyone at EPRI’s web site at http://intelligrid.epri.com/

The list of business models on p121 will require considerable computer science and software application authoring. Software development and modeling tools such as HLA and UML will be needed.

Fast Simulation and Modeling (FSM)

The grid will need to be able to automatically look ahead and anticipate problems, schedule events, and optimize its performance. Three capabilities will be needed by a self-healing grid (SHG):

• Look ahead simulation to anticipate and avoid disturbances.

• What if analysis for large-region power operations and planning.

• Integrate market, policy and risk analyses into system models and quantify their effects on security and reliability.

Open Communications Architecture for Distributed Energy Resources in Advanced

Automation A subset of the work on an IECSA is the development of an open communications architecture for distributed energy resources (DER) in advanced distribution automation (ADA) or DER/ADA architecture. The DER/ADA project will develop object models for integration of different types of DER into the open communications architecture.

Software engineering with an emphasis on object oriented modeling (OOM) using Unified Modeling Language (UML) will be needed.

Enabling Technologies p125

In addition to the IECSA foundation, EPRI has developed the following list of critical enabling technologies that are needed to move toward realizing IntelliGridSM.

Automation: the heart of the IntelliGridSM

Distributed energy resources and storage development and integration

Power electronics based controllers

Power market tools

Technology innovation in electricity use

The Consumer Portal

Automation: the Heart of the IntelliGridSM

Distribute Energy Resources and Storage Development & Integration

Power Electronics-Based Controllers

Power Market Tools

Technology Innovation in Electricity Use

The Consumer Portal

Conclusion

The participation of energy companies, universities, government and regulatory agencies, technology companies, associations, public advocacy organizations, and other interested parties throughout the world need to contribute to refining the vision and evolving the needed technology. Only through collaboration can the resources and commitment be marshaled to enable the IntelliGridSM.