Toppling outages the smart way
Argonne National Laboratory is testing software to predict electrical use in an attempt to prevent blackouts
chicagotribune.com
By Jon Van
Tribune staff reporter
September 26, 2003
Rather than stringing more electrical lines, researchers at Argonne National Laboratory say a better way to prevent another crippling power outage involves software that predicts problems before they happen.
In a radical approach, they are treating the nation's electrical grid as if it were like the Internet, where electrical demand is anticipated, and the flow adjusted before imbalances cascade out of control.
"We have 157,000 miles of transmission lines in the country, and it costs half a million dollars to build a mile of transmission line," said Lefteri Tsoukalas, an engineering professor at Purdue University, which led a team of engineers that developed the software Argonne is testing. "Half a million dollars buys a lot of information technology."
The development of a "smart" electrical grid would use extensive information about where electrical demand originated to predict anticipated demand in the future. These predictions would warn the system when trouble--like a massive blackout--may occur so it could be averted.
"What we've learned is this is doable," said Yung Liu, manager of energy technology at Argonne. "You get pretty good predictions."
Furthermore, as computer chip prices continue to fall, adding intelligence to the power grid is much cheaper than rebuilding it, said Tsoukalas.
The software Argonne is testing, called TELOS, looks at patterns of electrical use to learn how to predict future demand. Within a few years, the lab tests could be ready for the real world, according to the engineers.
Argonne has collected 30 months' worth of data of its past electrical consumption, which is correlated with hour-by-hour weather information.
A year's worth of data was used to train TELOS to understand Argonne's electrical consumption patterns. Now it is running simulations that predict power consumption, and those predictions are compared with the power demands that actually occurred.
Although the predictions aren't perfect, they have been fairly close to actual use, Liu said.
Using computers in the decision-making process is probably necessary to prevent massive power outages from spreading, he added.
"In a typical control room, you try to prevent cascading problems," Liu said. "But in some cases, you have only seconds to act--the blink of an eye. I don't think humans can do it."
Large, national power grids have become so complex that no one can monitor or control them adequately, Tsoukalas said. So instead of focusing on the overall grid, local grids would be monitored, and demand would be predicted on a smaller scale.
By correcting local problems before they spread, he said, operators can avoid major failures of the overall grid.
"If you see anomalies--feeders are overloaded, congestion--they can be corrected," Tsoukalas said. "But often they go unnoticed until it's too late."
Still, information technology alone won't solve all grid problems, he said. There must be adequate generation and transmission infrastructure in place, but adding computer intelligence to the system would vastly improve reliability and security.
"You could give every electric meter in the country an IP [Internet protocol] address," Tsoukalas said.
Although engineers long have used data to manage the electrical grid, turning the task over to computers would be a fairly radical move, said David Schooley, a senior engineer with Commonwealth Edison in Chicago, who worked with the Purdue-led consortium.
"I think it's a fundamentally sound approach," he said. "It's in the lab at this point and has to be developed more to be put into practice. This would be another step in software potentially making decisions, looking out ahead and doing something to alleviate a problem.
"Nothing we have now does that on a large scale."
The Purdue consortium was one of six formed to work on network reliability, an initiative launched in part as a reaction to a major blackout in the western U.S. and Canada that occurred in 1996.
The initiative's manager, Massoud Amin, said that technology developed by many researchers is being integrated into what he calls "the self-healing grid."
Amin, formerly a manager with the Electric Power Research Institute, an industry group, is an engineering professor at the University of Minnesota. The industry is very interested in moving to a self-healing grid, he said.
"It is alive and well," Amin said. "The smart grid is one of the enabling technologies that are part of creating the self-healing grid. This is no longer a distant dream, but something we can make happen over the next three to five years, depending upon funding."
Both government and industry groups are working to push the concept and secure funding to implement the self-healing grid, he said.
The utility industry has embraced smart elements in the power grid, said Ed Schweitzer, whose firm, Schweitzer Engineering Laboratories Inc., based in Pullman, Wash., makes protective relays and other components for electric utilities.
"We've pioneered using relays to talk to each other, to share information and do new things," said Schweitzer. "We've got bits and pieces to replace the slow-moving human factors."
Yet the predictive aspect of the TELOS software could make the grid smarter and more able to avert major outages, he said.
"The grid doesn't need to be rebuilt," Schweitzer said, "but it certainly needs to be augmented."
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