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Beyond the Supply and Demand Curves
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Within the report, however, is clear evidence that the entire nature of system reliability become more complex and evolved in ways that a simple balancing of supply and demand curves just cannot capture or express. NERC was quite detailed in describing steps that have been taken to enhance reliability in the wake of the August 2003 blackout. Despite Gent's assurances that, "We are confident that we have a stronger system today and going forward than we did last summer," it is clear that much more must be done.
The big numbers from the NERC report tell a story of shifting but stable resource equilibrium. While electricity demand is expected to grow by about 69,000 MW nationwide over the next five years, new generation capacity will mostly pace that growth at 67,300 MW. Transmission construction is also on an upswing, noted NERC, with more than 10,000 miles of new high-voltage transmission on the boards for installation between now and 2013, a nearly 5 percent increase in line-mileage for systems 230 KV and above.
Will that be enough? Enough to maintain network reliability, the NERC report suggests, although, "some portions of the grid will not be able to support all desired electricity market transactions." What this means is that regional seams and local constraints continue and might not get much better soon, that there will be times when system needs outweigh transactional needs, and that market participants may expect continuing bottlenecks, congestion and higher costs.
The meat of the NERC resource adequacy assessment comes in the details of reports from each of the reliability control areas within the big three regional interconnections. For the most part, there will be adequate reserve margins and capacity margins next summer with some marginal decreases by 2009. Some areas will have less of a cushion as time passes, although how critical that becomes for reliability or market purposes is hard to assess right now.
"The system is closer to its limits," acknowledged David Nevius, senior vice president of NERC. Transmission expansion has not proceeded at the same pace as generation and load growth. "That doesn't automatically lead to less reliability, but we will have to monitor the grid more closely."
Of particular interest in the NERC report is the section titled, "Implications of Operating Near System Limits." Here the less-quantifiable aspects of reliability are given form and attention: Coordination and communication among operating entities, better training, adherence to operating standards, improved reliability assessments, and the use of new technologies to better understand and control real-time conditions on the grid.
More than a mere match of demand and supply, this is where the minute-by-minute control over networks can enable more efficient use of existing resources and better responses to emergency conditions when they arise. For example, this is a list of tests and analysis that NERC now considers essential to understanding the "strengths, weaknesses and overall operational preparedness" of the grid:
While this list recommends a far more sophisticated sense of the grid, NERC also points to continual improvements to the tools and techniques used to capture that knowledge and that allow operators to better manage the transmission system.
Tools such as state estimators, which aggregate real-time data from thousands of points across the grid, are becoming more commonly used. Ideas emanating from one region are migrating to others. An example is a wide-area monitoring system (WAMS) developed by the Bonneville Power Administration but now being used in the Eastern Interconnection in a pilot sponsored by the U.S. Department of Energy, the Consortium for Electricity Reliability Technology and NERC.
Other notable developments include improved technologies for monitoring dynamic ratings for transmission lines, special protection systems, reactive power planning, and power system stabilizers. The goal, according to NERC, is not just to know the current state of the system but also to be able to respond to contingencies both expected and unanticipated. “The rapidity with which the state of the electrical grid can change demands that an operator be concerned as much with the future state as with the current state of the system,” observed the NERC report.
The ideas are there and the technologies, in many cases, are on the shelf and ready for installation. The key is finding the support for resource expenditures that are not easily categorized as new power plants or miles of transmission lines.
The Bottom Line: Louise McCarren, the chief executive officer of the Western Electricity Coordinating Council, told me that she had just returned from a Boston conference on transmission reliability technologies, co-sponsored by the New England ISO and the Massachusetts Energy Bar Association, in which these very issues were discussed. "If these technologies work they way they say they do, we can fix reliability problems," McCarren said. "But why aren’t people spending money on them?"
One possible answer appears in the agenda description for the panel on "Financing the Next Round of Infrastructure" that took place during the conference. "[T]he financial community, after experiencing losses in the early stages of restructuring, will need to be convinced that it can make money on those investments."
Arthur O’Donnell is the Editorial Director, newsletters, for Energy Central. The Business Electric is found exclusively on Energy Central.
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