The key to developing a smarter power grid is to standardize and integrate two systems: the power and energy delivery system and the information system that controls it. IntelliGrid is a response to that need.
lectricity industry stakeholders are increasingly concerned with the current state of the global electricity enterprise and the infrastructure for which it is responsible. The existing electricity supply system is aging, under stress, often not well maintained, and being physically used in ways for which it was not designed. Since the 1970s, electricity sector stakeholders have become polarized, the industry’s commitment to long-term planning and development has eroded, and its credibility has suffered.
Lack of critical infrastructure investment and surging demand for electricity is taxing the electric power system to its limits. Over the last decade, growth in US electricity demand has exceeded new transmission capacity by more than 15 per cent. In addition, microprocessor-based technologies have radically altered the nature of the electrical load, resulting in demand that is incompatible with a power system created to meet the needs of an analog economy. This has led to new quality and reliability problems, and more than a $100 billion in losses to US industry and society annually.
Aims of IntelliGrid
The IntelliGrid Consortium is a collaboration of energy, high-technology and government leaders, working to address these issues and begin to develop an intelligent, self-healing power system.
The foundation of this new system is the IntelliGrid architecture – an open-systems-based comprehensive reference architecture. It will integrate intelligent equipment and data communications networks into an industry-wide distributed computing system. It is the fundamental basis for enhanced system capabilities.
Parts of this system are already in place in some utilities, but there is a wide range of variation in the level of capability and compatibility across the power system. Generally, system integration and coordination are not performed on a wide enough scale to address the severity of the problems faced by the grid, as is clearly illustrated by analysis of previous blackouts.
IntelliGrid Architecture brings together the energy and IT worlds
In the past, the power delivery system has been a primary focus of development. The IntelliGrid Architecture is intended to integrate two systems in the power industry: the power and energy delivery system and the information system (with its communication, networks, and intelligence equipment) that controls it. These systems must be developed in parallel.
By applying the latest systems engineering methods, and computing and communications tools, IntelliGrid will be able to cut across traditional operating boundaries, promoting greater interoperability; improving performance and asset utilization; and ensuring better levels of robustness, responsiveness and security.
To maintain the flow of secure, digital-quality, highly reliable and available power, the IntelliGrid must be constantly self-monitoring and self-correcting. In the case of a disruptive event, the system should allow rapid recovery of the power delivery system and markets. At the same time it must be able to maintain the confidentiality of business information and the privacy of consumer information.
The current information infrastructure of the energy industry is plagued with legacy systems, proprietary protocols, stranded applications, and ad hoc interfaces. This jumble impedes the expansion and upgrading of computer systems, software applications, and new equipment. The IntelliGrid Architecture, therefore, identifies a recommended approach to add new applications that are readily integrated and to replace the jumble of legacy interfaces with common ones, providing lower-cost solutions as the information infrastructure grows in extent and complexity.
The IntelliGrid Architecture will benefit the industry through:
- Advanced applications that will require a ubiquitous infrastructure
- Capital savings from standardized components that can be competitively procured
- Life-cycle savings from lower maintenance costs due to standardization
- Reduction in stranded assets from systems that can be integrated
- Ability to manage development through incremental steps and then large scale-up
- Reduced development costs
- Robustness achieved from structured approaches to systems management
- Enabling the energy industry to be consistently and adequately secured.
In basic terms, the IntelliGrid architecture is a set of high-level concepts that are used to design a technology-independent architecture, as well as identify and recommend standard technologies and best practices. Object models and modelling guidelines are used to give standardized names to data and to describe their relationships, their formats, and their interactions in standardized ways. Network and system management is used to monitor and control the information infrastructure in a manner similar to the monitoring and control of the power system. Data management technologies and best practices ensure data consistency across dispersed systems as more reliance is placed on automation.
To manage the diversity of systems and the migration to systems with standardized interfaces, the new architecture must take a ‘technology independent’ approach. The energy industry has some unique information requirements and some common to many industries, so the IntelliGrid Architecture cannot recommend a single set of standard technologies for use everywhere in the industry. Instead, it categorizes these special requirements as IntelliGrid architecture “environments,” defining each environment according to its common requirements and identifying the standards that are appropriate for each.
The results of the IntelliGrid Architecture project are contained in a series of printable documents, computer models, and web-browser navigable hypertext pages. Key aspects, along with the environments and their links to the standard technologies, were incorporated into a modelling tool. The tools and information, along with utility examples, are available from the website at www.epri-intelligrid.com.
Evolving the grid
There are a number of critical enabling technologies needed to allow the IntelliGrid to evolve. They include automation, communication architecture, distributed energy resources, power electronics-based controllers, power market tools, technology innovation and the EnergyPort. Aspects of some of these enabling technologies are under development. Others require renewed support for research.
The so-called ‘EnergyPort’ is the consumer gateway, which is now constrained by the meter but which in the future architecture will allow price signals, decisions, communications, and network intelligence to flow back and forth through a two-way portal. This is the linchpin technology that leads to a fully functioning retail power marketplace with consumers responding (through microprocessor agents) to price signals.
The EnergyPort would enable two-way, secure and managed communications between consumers’ equipment and energy service and/or communications entities. It would perform the work closely related to “routers” and “gateways” with added management features to enable energy industry networked applications.
Specific capabilities of the EnergyPort include pricing and billing processes that would support real-time pricing.
For the utility, consumer energy management through sophisticated on-site energy management systems managed through the EnergyPort can improve real-time system operations, including dispatch, demand response, and loss identification. This data will also enable both short-term load forecasting and long-term planning to be upgraded. For the consumer, the port will be able to manage value-added services, such as billing inquiries, service calls, outage and emergency services, power quality monitoring, and diagnostics.
The port is also an important step in developing a simple “plug and play” connection for distributed energy resources. Small power generation and storage devices distributed throughout the power delivery system, and integrated with it, help strengthen the power delivery infrastructure, provide high-quality power, provide a range of services to consumers, and provide consumers with lower-cost, higher quality power. Distributed storage technologies address the inefficiencies inherent in the fact that otherwise electricity must be used at the instant it is produced. However, there are many challenges to be met to develop ways of seamlessly integrating these devices into the power delivery system, and then monitoring and dispatching them effectively.
Automation will play a key role in providing high levels of reliability and quality while enhancing security and enabling availability of a range of consumer energy services. To a consumer, automation may mean receiving hourly electricity price signals, which can automatically adjust home thermostat settings via the EnergyPort. To a distribution system operator, automation may mean automatic “islanding” of a portion of the distribution system with local distributed energy resources in an emergency. To a system operator, automation may mean a self-healing, self-optimizing power delivery system that automatically anticipates and quickly responds to disturbances to minimize their impact, minimizing or eliminating power disruptions.
Several utilities are already benefiting from IntelliGrid’s methodology tools and recommendations
Standardized communications architecture must first be developed and overlaid on the existing power delivery system. This integrated energy communications system architecture is an open-standards-based systems architecture for a data communications and distributed computing infrastructure
Based on solid state devices, power electronics controllers offer control of the power delivery system with the speed and accuracy of a microprocessor. These controllers allow power system operators to direct power along specific corridors, meaning that the physical flow of power can increasingly be aligned with commercial power transactions. Power electronics-based controllers can substantially increase power transfer capacity by eliminating power bottlenecks, extending the market reach of competitive power generation.
To accommodate changes in retail power markets, market-based mechanisms are needed that offer incentives to market participants in ways that benefit all stakeholders, facilitate efficient planning for expansion of the power delivery infrastructure, effectively allocate risk and connect consumers to markets. For example, service providers need a new methodology for the design of retail service programmes for electricity consumers. At the same time, consumers need help devising ways they can participate profitably in markets by providing dispatchable or curtailable electric loads, especially by providing reserves.
Taking an IntelliGrid approach
Although the IntelliGrid Architecture is is still being developed, power utilities can position themselves now to make full use of it in the future. They can formally adopt the architecture as the strategic vision for utility information infrastructure, and ensure that potential users of the architecture understand how to use it and apply the functional descriptions and high-level concepts.
As with any new system, it is necessary to develop a plan to implement technology-independent architecture using the recommended standard technologies, based on business needs, the appropriate timeframe and financial constraints. Planning is also required to migrate legacy systems and interfaces to the IntelliGrid Architecture.
There are profound opportunities for technological innovation to transform the reliability, security, and value of electricity for the coming century. However, there is a large and growing gap between the performance capability of existing electric power systems and the needs and expectations of modern society. Fundamental to resolving this gap is a commitment to restoring the level of infrastructure investment needed to fully develop and deploy new systems such as the IntelliGrid.
Clark Gellings and Kurt Yeager, Electric Power Research Institute, California