Sandia LabNews

Sandia-led study recommends predictive modeling tools to head off future power failures

Market restructuring and increasing complexity of the power grid raise concerns about power reliability

Now that the Y2K transition is safely past, you might want to put those extra candles and flashlight batteries back in the bottom drawer . . . but don’t.

The nation’s electric power grid is growing increasingly complex and interconnected, with a greater number of power buyers and sellers making a burgeoning number of transactions. And restructuring of the electric utility industry is bringing uncertain changes in the way the grid is managed.

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POWER GRID OF THE FUTURE — Were widespread power outages last summer an advance warning of the type of reliability problems the nation’s power grid may experience as the electric utility industry transitions to a restructured market? A series of DOE studies, including one study led by Sandia, recommends preemptive changes in the way the nationwide grid is managed as a system. (Photo by Randy Montoya)

To the average person, that means the lights might go out more often and the power outages could last longer unless utility companies can cooperatively find ways to monitor grid traffic and recognize the factors that lead to failures sooner, according to a recently released Department of Energy study by Sandia and other members of a DOE team.

Traditionally, power companies use simple, worst-case-avoidance software tools to monitor how power is flowing from place to place and to watch for the telltale signs of imminent outages. Realistically, though, it’s the been-there-done-that experience of plant operators that fends off most potential power failures.

"The software tools power companies use to monitor and control the electric grid were not designed for the level of complexity and the number of transactions the system is experiencing today," says Abbas Akhil (6201), a member of a DOE-wide team looking at electric grid reliability issues. "It’s clear that the deterministic software tools available today are not adequate for predicting and averting major outages in the future."

US power users might already be seeing the effects of changes in the power industry. Last summer eight separate major power outages in different regions of the country occurred within weeks of each other. The outages affected millions of people, resulted in several lawsuits, and cost power users untold millions in lost business and productivity, says Kevin Stamber (6235), who helped DOE study the causes of the outages. It was the first time widespread stresses on the US power grid, in this case increased electricity use prompted by sustained high temperatures across the country, caused system-level failures, he says. "These really are an advanced warning of the type of reliability issues we may experience as we go from a regulated market to a competitive electric market," says Margie Tatro (6201), Deputy Director for Energy and Critical Infrastructure Programs. "It points to the need for a new way of thinking about the power grid as a system."

The DOE report concludes that current deterministic grid-monitoring tools are becoming outdated and that a new, more sophisticated power grid command and control system is needed. At the heart of that system should be a new set of software tools based on probabilistic risk assessment methodologies that include a variety of mathematical models, including those that simulate load flow, dispatch options, weather factors, contingencies, and more, according to the report.

Probabilistic risk assessment software and models could help plant operators better understand where to dispatch power, how much reserve is appropriate given the weather and other factors, how dispatches are going to affect other parts of the grid, what the contingencies are for potential failure scenarios, what the economic impacts are of dispatching, what the effects of new power plants coming on line would be, and more.

It would, in a sense, help plant operators predict the future, or at least quantify the likelihood of something happening and test the effects of responses hours or days in advance. "In today’s environment, we need faster tools to evaluate the grid and plan for contingencies based on probabilistic methods," says Abbas.

The report also suggests further study of a "distributed power grid": the idea that hundreds of traditional and nontraditional generation sources and storage devices could supply power to the grid at various times and locations, enabling less reliance on mega-scale power plants and giving the grid a broader, more stable foundation.

Nationwide reliability study

DOE’s Transmission Reliability Program was spurred by an electric utility industry request to study grid reliability issues and trends relating to the transition to a restructured market. In addition, a Sandia-led analysis of DOE’s energy R&D portfolio pointed to a need for a program to improve the nation’s electric grid reliability.

The result was formation by Sandia, Lawrence Berkeley National Lab, and Southern California Edison of a Consortium for Electric Reliability Technology Solutions (CERTS), now made up of electric utility company, university, and national lab experts, including Sandians, to study and recommend solutions to grid reliability issues.

Each CERTS participating institution became lead on one written report, resulting in a set of six white papers that were finalized and released by DOE in November. The papers’ topics range from technical hardware issues to an economic view of open market trends.

Sandia’s paper, titled "Accommodating Uncertainty in Planning and Operations," compares the relative uncertainties in both the regulated and restructured business environments and recommends the new software tools to manage the higher degrees of uncertainty inherent in a restructured market.

In addition, Energy Secretary Bill Richardson formed a Power Outage Study Team (POST) in August to examine the circumstances surrounding each of last summer’s power outages, how utility companies responded to them, and their economic consequences. In a bit of serendipity, Kevin already had compiled 300 pages worth of data about major recent power outages, including those of last summer. His work was used by the DOE teams as baseline data, which put Sandia at the heart of the POST project. POST results were released in January in a series of public meetings.

"Electric grid reliability is a perfect issue for Sandia and the national labs to be studying," adds Margie. "There is potential for major financial disruptions in this country because we are putting stresses on our infrastructures they were never designed to handle."

"It’s difficult for private industry to justify investments in the protection of our critical infrastructures given the nature of their markets today," adds Sam Varnado, Director of Energy & Critical Infrastructure Center 6200. "Sandia is positioned to explore these issues and help industry establish a business case for investing in protection. We can also offer the private sector some of the most cost-effective protection options." (See "Critical Infrastructure Protection initiative picks up steam" above.)

Last modified: February 23, 2000