By Terry Nielsen and Don Hall
Today, almost every distribution utility is investing significant capital to automate the processes that deliver electricity to residential and commercial customers. New developments in energy technologies are providing practical opportunities for utilities to better serve customers by applying distribution and substation automation (see Figure 1), advanced automated meter reading, load management and other power systems automation and control technologies.
But just how far along are utilities in actually applying these technologies? And how will the introduction of these technologies affect how utilities manage the distribution of electricity in the future? What information strategies are being deployed to unite this mix of what META Group’s Energy Information Strategies group calls the emerging “geodesic network?”
To answer these questions, CES International recently surveyed its customer base. Findings of the survey, which was conducted in conjunction with the CES International advanCES 2001 conference, confirm the need for what the market has coined “Energy Delivery Management.”
Increased Network Complexity
Society has come to depend on no other single product more than electric energy. While electric power consumption has grown at a robust rate over the last two decades, the demand for highly reliable electric service has increased even faster. The advent of the integrated circuit, home electronics, the central processing unit (CPU), the personal computer, computer-controlled manufacturing processes, the Internet and the e-business economy have converged to require virtually uninterrupted, pure electric power.
In parallel with these demand-side developments, the power industry’s delivery side is moving away from monopolistic structures toward more competitive business models. Yet the design and configuration of the delivery systems remain largely unchanged from the 1960s, when power interruptions were mostly considered nuisances—if they were noticed at all. All of these factors are driving research, development and deployment of new power technologies in combination with innovative service offerings. As a result, we have experienced a dramatic increase in the complexity of managing power delivery systems.
At the recent advanCES user conference, CES International surveyed its customers and confirmed these findings. The survey revealed that the introduction of automation technologies is making distribution management more complex than ever before for utilities. Of those surveyed, nearly 83 percent said that over the next five years the complexity of operating their electric distribution systems would grow either “very rapidly” or “somewhat rapidly.” Only 18 percent said the complexity would grow slowly (see Figure 2).
Similarly, respondents largely agreed that operating their electric distribution system would become more “dynamic.” A full 84 percent said that over the next five years their network operation would become more dynamic, while only 3 percent said less dynamic. Thirteen percent predicted no change.
Managing Power Systems
Managing the delivery of electric energy has never been simple. Delivery systems are often thought of in terms of the physical “plant,” but a better analogy may be a biological system. Like a biological system, an energy delivery system operates in a state of constant change with resources distributed through space. They consist of thousands of components, each with a small but interrelated part to play. They tend to be very susceptible to external events, and maintenance/repair is typically accomplished without shutdown. Thus, there has always been an inherent level of complexity in the management of energy delivery systems. Several new drivers (and some older ones being more highly emphasized) are leading to exponential increases in this complexity. These include deregulation, aging infrastructure, new power technologies and retail competition.
The “New” Reliability Imperative
The reliability of an energy delivery system traditionally has been defined by the continuity of service that the energy consumer experiences. Couched in terms of frequency and duration of interruption, reliability typically has been measured based on past performance (historical assessment method) of the delivery system over a period of time (often a rolling three-year period). Movement toward predictive analysis is under way, where the reliability of different system designs are compared based on the predicted reliability of each.
With the proliferation of digital electronics throughout industrial, commercial and residential market segments, how well the power is delivered during continuous service (power quality) is coming under close scrutiny. Abnormalities previously unnoticed by the consumer—voltage sags, swells, surges, harmonics—have been identified as causes of consumer end-use devices and associated processes ceasing to operate. From the consumer perspective, they experience service interruptions regardless of whether there is an interruption in service.
For the end-use consumer, the line between continuity of service and power quality has become blurred, if not totally indistinguishable. Combining the two concepts—continuity of service and power quality—results in a description of an overall quality of service (QOS) as perceived by the consumer, but is still missing an important aspect of consumer perception—price.
Price encompasses what the consumer is willing to pay for in terms of QOS. Extremely high QOS is technically feasible-approaching the level of one disturbance per century. But achieving that high QOS level is also very costly—approaching 50 times the cost of normal delivery. Although most consumers would like to have this QOS level, very few would be willing to pay for it. QOS combined with price describes the consumer’s overall perception of electric service. From the delivery company’s perspective, balancing the varying QOS requirements against the cost to provide or not to provide defines an “economy” of service.
Historically, management of QOS—the combination of reliability and power quality—has been approached from the planning and design perspective. Delivery systems were built to provide “static” QOS with some margin to account for the unknowns. In addition to the gains made from the “planning” approach, significantly more benefits are available with real-time dynamic management of QOS and economy. Effective management is enabled by the ability to manage risk—the likelihood of violating QOS and/or economy targets. Margins can be reduced, deferring capital projects, therefore resulting in a “leaner” delivery system operating with significantly improved efficiency, lowering costs and increasing the financial health of the energy delivery company.
Figure 3 depicts the results from one question asked in the CES customer survey: Do you see future incorporation of “risk-management” strategies into the operation of your distribution infrastructure? Survey respondents answered a fairly resounding “Yes” to that particular question.
Market-responsive vs.Market-reactive Decisionmaking
Decisions are typically made considering two main elements: a specific range of base information that establishes the context of the decision, and a stream of events or changes that affect the base in a predictable manner. The stream of events essentially corresponds to a “window in time” over which the dispatcher’s or operator’s tasks, tools and information must be coordinated to support decision-making.
System support for operations’ decision-making can be generally defined within one of four “time windows:” historical assessment, reactive decision-making, proactive decision-making and predictive assessment. Predictive assessment-the premise or end game for the deployment of an energy delivery management decision-making framework-provides for continuous evaluation of the delivery system’s operating state, comparison against on-going forecast and analysis of potential future events, and course correction to avoid problems and remain within an acceptable zone of reliability, all in real-time.
The 21st century brings a move to more proactive/predictive electric power delivery system management model that enables the following:
- Continuous performance assessment and management,
- Combined objectives of risk, quality and economy to achieve reliability,
- Efforts to avoid regulatory and other penalties,
- Real-time assessment and course correction of the operating state, and
- Frequent predictive assessment of reliability in terms of security, quality and economy.
The enabling energy delivery management systems of the future will acquire the roles of brain and central nervous system interacting with the dispatchers/operators who assume the role of advisors with options for varying degrees of intervention. It is inevitable that our power systems will become more complex, but proper management of those complexities will result in a more efficient, reliable system overall.
Terry Nielsen is CES International’s senior vice president, product strategy & quality, and Don Hall is CES International’s energy delivery management product manager.