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Just as the telecommunications industry in developing countries has leveraged the latest mobile technology to leapfrog beyond aging legacy systems in developed countries, Africa offers intriguing possibilities to deploy and interlink the latest and most innovative energy technologies to create an energy infrastructure that is highly distributed, heterogeneous, robust, and sustainable.
In this article, challenges are discussed for secure smart energy grid and automation systems from cryptographic technique viewpoints.
A comprehensive polling of industry leaders around the world finds that North America leads in energy storage, while Europe is ahead in distributed generation and microgrids. Energy management systems, distributed management systems and communications technologies will be critical to full realization of all the anticipated smart grid benefits.
In the last few years, novel control concepts have been proposed with the goal of making distribution networks more flexible by introducing active control mechanisms. Active control is expected to help with maintaining the health and stability of the power grid even after disturbances, loss of equipment or other unforeseen situations, by undertaking proactive actions to preserve the stability of the power network.
Let's hear what the Grid has to say about its own evolution, and the potential it sees locked away in all that data. The author puts on his sci-fi hat and imagines a conversation with the Grid about a specific technology – synchrophasors – and how they will change the way the Grid interacts with control room operators.
Traditional utility rate setting is arguably incompatible with innovation in electric power transmission and distribution. But there is a ready solution: performance-oriented ratemaking that supports innovation, measures operational results and rewards performance.
A grid that incorporates computing and communications intelligence unfortunately presents potential attackers with many new opportunities, requiring a holistic approach to security that takes both hardware infrastructure and software into account. Fortunately, researchers are addressing these new issues on a broad front.
An assessment done four years into a seven-year program confirms the general effectiveness of demand-response, but identifies challenges with the business case for some technologies such as in-home displays. Conservation Voltage Reduction is proving to be an unanticipated cost-effective beneficial resource, while energy storage is found to be technically effective but still at the outer boundary of cost-effectiveness. With over two more years to go, the EPRI demonstration program will also assess virtual power plants and encourage more rapid smart grid standardization.
A major study of reliability trends shows that power interruptions have increased at a steady rate of about 2 percent per year over a period of ten years. These findings stand up robustly to analysis of measurement error and bias, and set the stage for study of what causal factors are at work.
Smart dispatch tools, advances in customer consumption management techniques and storage technologies can help offset operational challenges and energy price increases associated with the adoption of cleaner, lower-emitting and renewable supply resources.
The ability of a utility to create ubiquitous connectivity between all of its current data sources and decision-making systems is essential for the success of smart grid deployments. Yet the characteristics and performance requirements for wide-area networks are quite complex due to the multitude of grid applications and enterprise applications that are essential to utility operation.
As the country's principal utility, the State Grid Corporation of China (SGCC) is dedicated to developing a smart grid, to promote clean energy, elevate energy efficiency, tackle climate change and reduce emissions. SGCC has launched a comprehensive program to build what it calls a Strong and Smart Grid, putting major efforts into grid planning, testing and research systems, demonstration projects, international cooperation and standardization.
The European e-GOTHAM project aims at developing open source smart energy management middleware for controlling and monitoring prosumers' energy consumption and production, through a behavior-driven and context-aware decision approach. It will be implemented in three pilots, in the industrial, services and residential sectors.
PMUs with high sampling rates and GPS synchronization represent a critical smart grid technology that can enhance transmission system operations by providing wide-area monitoring of power system dynamic behaviors, an ability that was unavailable until recently. The New England Independent System Operator is two years into a project to expand synchrophasor infrastructure to give system operators a view of what is happening over the region's 3400 kilometers of 345-kilovott transmission lines.
Oncor's Smart Grid Applied Systems program focuses on the modernization, automation and integration of distribution operations control centers. It is designed to leverage the significant investment that Oncor has already made in AMI and feeder automation. The program, comprising mobile workforce management, outage management, distribution SCADA and distribution network analysis, is a cost-effective step toward a smart grid.
Smart grid deployments are creating exponentially more data for utilities and giving them access to information they've never had before. We need to know how to warehouse data offline from the operational database, organize data for efficient data analysis and reporting, provide access to operational data on a broad scale at minimal cost and isolate other business users from critical operational systems.
With little prior experience to draw from other energy companies, the Sacramento Municipal Utility District is trying out a wide array of smart grid technologies. The goal is to develop a roadmap for large-scale deployment. Prominent elements include smart metering, time of use and peak pricing, microgrid islanding and energy storage.
Make sure top management is onboard from the start; spell out all the operational implications of investments made; see that qualified managerial staff are available to complete all required tasks; adopt a business process methodology; and, not least, have a comprehensive plan.
Prospects for wide integration of energy storage into grid systems will be enhanced with the development of market mechanisms that allow for coordinated trading of charge and discharge time. However, introduction of such mechanisms represent a challenge to traditional thinking and require added complexity and computation. Conceptually, energy storage straddles our conventional categories of transmission, distribution and generation.
Traditional distribution automation typically consists of feeder devices such as reclosers, switches, fault current indicators and capacitor banks, which improve reliability and network performance. However, a major obstacle to realizing many automated functions is the lack of a ubiquitous communications network across the distribution grid. To overcome this barrier, utilities are eying the synergistic benefits advanced metering can bring.
Energy storage can contribute to the smart grid by facilitating integration of renewable sources and provision of important ancillary services. At the same time, energy storage cannot really be exploited to its fullest potential without a smart grid infrastructure capable of managing bidirectional energy flows. Because of that reciprocal relationship, energy storage and the smart grid represent an indispensable synergy.
The temperatures of transmission lines have traditionally been estimated by means of ampacity tables that are calculated from expected average weather conditions and values that have been considered valid for a whole season. But in reality, a conductor's position and temperature vary greatly with weather conditions over much shorter time intervals. One solution is to base real-time estimates on instrument readings, but an even better method uses software to calculate the mechanical and thermal status of the conductor.
The initial focus is on improved distribution management in the area around Harrisburg. Ultimately, monitoring devices and wireless communications will be installed throughout the utility's operating area to improve reliability and efficiency and allow for more flexible and capable management. The U.S. Department of Energy, which has provided support for the project with funds from the 2009 stimulus bill, is being kept closely informed of progress.
The constant variations in line and source topologies found in a typical automated distribution feeder can create design challenges for protection engineers, especially those using traditional overcurrent protection methods. A novel approach using differential protection recently debuted on an A&N Electric Cooperative feeder in Virginia, demonstrating the ability to reduce the number of required settings groups without compromising feeder flexibility or the speed, accuracy, and selectivity of protection.
With all system infrastructure in place and utilities finishing up the installation of smart grid asset systems across the Pacific Northwest region, a transactive control system will "go live" this fall, allowing the installed assets to start responding to electric power conditions. Though questions will remain, we believe we are taking a significant step that will move the nation closer to a more efficient, sustainable and resilient power system.
Power grid information processing is becoming increasingly important as we transition to smart grid architectures that collect and analyze massive data. Groups at Oak Ridge National Laboratory have developed tools to help utilities manage the greater flows of information. But the data collection and analysis center itself could become a failure point during major disruptions when situational awareness is most desperately needed. Ultimately, cloud-computing infrastructure will allow for secure virtual information and analysis centers that can distribute results to a large number of analysts, including operational personnel, regardless of their physical locations.
The challenges to distribution planning in harnessing some smart grid technologies are described at a high level, with observations about the potential impacts and lessons that distribution utility executives and planning engineers can expect in the years ahead. In effect, distribution planning faces complex analytical challenges of a kind long familiar to transmission planners.
The power system infrastructures in Europe and the United States have attained a venerable age, and as a result, many components are due for replacement. At the same time, the way in which components are operated changes drastically in a smart grid setting. How then can we ensure sufficient reliability for the grid of tomorrow? We claim that operational monitoring of key components is a necessary requirement.
A really smart grid will, among other things, allow network control strategies to be adjusted to a dynamically changing environment so as to meet the requirements of all stakeholders. The adoption of advanced techniques that are being developed in the semantic web initiative will make grids more intelligent by automatically adjusting the situation of the network to the connection and to the removal of resources available to participate in the operation of the network.
As generally envisaged, the smart grid is not only a complicated system made of many parts, but also a complex system—one in which overall behavior cannot not be directly inferred from the behavior of the individual components, and one that no single entity can control, monitor and manage in real-time. Because it is complex, distributed control is more than a convenience; it is required.
As power resources become more distributed, systems more conducive to demand-response, and generation more intermittent, efficient and robust system operation will depend critically on the ability of new dispatch methods to provide a better predictive, forward-looking and holistic view of system conditions and generation patterns.
Advanced metering with two-way communications has the potential to make meters a core element of an integrated system to better manage utility services. But what kind of communications are appropriate? Smart meter traffic is characterized by small session duration, limited mobility and large number of devices, and as such is not handled efficiently by existing wireless broadband access networks run the usual way.
Can a system designed for automatic meter reading be economically expanded or upgraded to implement future added-value capabilities without requiring a major overhaul, a large increase in capital expenditures and future added utilization costs? The question is timely and urgent, as smart metering gradually becomes ubiquitous.
The power industry is moving to develop the smart grid so as to keep up with the global economic growth. This movement will be more beneficial and sustainable to the extent we can secure the power systems of the future. Computational Intelligence, representing a comparatively new era of IT, can make grids really smart.
The smart grid requires seamless integration of software and hardware components and can be viewed as a cyber-physical energy system that integrates information and energy flows. Accordingly, it makes sense to do research on the development of applications to monitor and manage those flows. Two such applications borrow from a theory developed to support task scheduling over the Internet with a vast number of servers.
The Energy Systems Integration Facility (ESIF) will be the first laboratory in the world to enable smart grid equipment to be tested on a plug-and-play basis at megawatt levels. Newly invented equipment will be evaluated for compatibility with existing and future technology, and for robustness under varied operating conditions. A high-performance computer will allow for simulations and a SCADA system will monitor and control facility-based processes and gather and disseminate real time data for collaboration and visualization.
Pilot projects are exploring the potential of microgrids to make power systems less vulnerable to costly disruptions. Yet, if the grid is to be made much more decentralized, large investments in technology and training will be needed, and standards, such as IEEE 1547.4, will have to be developed.
The introduction of distribution-level marginal prices promises to have transformational impacts on power systems in terms of electricity costs, infrastructure resilience and the wide integration of renewable generation and sustainable new loads such as the electric vehicles. But to achieve the full range of potential benefits, it will be essential to adopt the right pricing structures and market reforms.
Data collection in Advanced Metering Infrastructures (AMI) presents new opportunities for utilities but, at the same time, can compromise the privacy of electricity consumers. Data aggregation can alleviate this challenge by combining collected sensitive data into a single representation; however, the accountability of individual smart meter data can be lost because an attacker can falsify aggregates without being easily detected.
Advanced metering infrastructure is a cornerstone of future grids, but the smart grid encompasses much more than the most frequently mentioned features connected with AMI such as increased communication capabilities, monitored infrastructure, improved fault recovery and self-healing capabilities. It also involves completely new processes and schemes to improve economic efficiency in coordinating the interests of all different stakeholders. Through the establishment of well-designed markets on all levels, and on most time horizons, the power system can become more efficient and greener, as well as smarter.
While opinions may differ about whether there is a single "right size" for smart grid demonstration projects, most will agree that a village is too small and countries too large to produce meaningful results. University campuses and communities represent an appealing intermediate scale, with enough diversity to put claimed benefits and costs to the test, as well as the intellectual resources to devise innovative approaches. An ambitious program at the University of Minnesota is showing how this can be done.
Machine learning techniques can be applied to sensor data collected from smart homes to reveal activity patterns of the residents, which can then be correlated with measured energy consumption. By associating activities with energy use and costs, intelligent systems can be devised to automatically control home environments so as to improve energy efficiency and cut expenses.
To improve the self-healing capability of the distribution-level smart grid in United States, the distribution outage management system has been evolving with exploration of two complementary technologies: feeder level fault detection, isolation and service restoration; and smart meter-based outage analysis. Both technologies are essential to elements in any smart grid blueprint.
The smart grid implies automation of the electric power grid, involving analysis of energy usage patterns to achieve data-driven management in real time. But automation often implies computerization, bringing in new cyber security risks if proper thought is not given to system design at the very outset. Security issues and lessons to consider include source code security, security as risk management, and how to move beyond defensive behavior to proactive procedures.
Although advanced metering infrastructures enable more dynamic generation, distribution and consumption, smart meters, wireless repeaters and routers must operate in physically unprotected environments and communicate with potentially hostile consumer systems. What is more, expanded bandwidth requirements tempt system designers to rely on non-dedicated and often un-trusted networks because of their lower costs. A combination of expanded cyber dependencies and greater public exposure will increase potential impacts from software vulnerabilities discovered within these systems. Thus, software vulnerability management is more problematic than ever.
As we all know, today's smart grid initiatives have given rise to multiple emerging products and services from a growing number of suppliers. Utilities want choices among vendors' products. As smart grid technologies mature, the need to ensure interoperability of products from multiple vendors will become significant. Although standards-setting organizations strive to provide a level of safety, quality and consistence in their products, traditional laboratory environments cannot guarantee that products form multiple vendors will interoperate smoothly when combined in the real world. As smart grid interoperability standards are relatively new on the scene, it is all the more important to ensure the end-to-end integration and compatibility of technologies to be deployed.
Emerging smart grid technologies are accelerating the transformation of the distribution system into the smart distribution system of the future. New operating techniques and design practices will be developed to continue improving the reliability of the distribution system. Engineers will develop tools and applications to be integrated with today's technologies so as to ensure the resilience of the distribution system and to achieve a self-healing grid.
In the journey towards a smarter and more dynamic operational future, distribution utilities will have to significantly modify traditional practices of protection and control. Fortunately, existing and emerging standards offer a clearly demarcated pathway to the new world of automated power delivery.
A monthly publication, the IEEE Smart Grid Newsletter features practical and timely technical information and forward-looking commentary on smart grid developments and deployments around the world. Designed to foster greater understanding and collaboration between diverse stakeholders, the newsletter brings together experts, thought-leaders, and decision-makers to exchange information and discuss issues affecting the evolution of the smart grid.
