For operators, a daily high-wire act

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For Operators, a Daily High-Wire Act

By Peter Behr, Washington Post Staff Writer

Wednesday, August 22, 2001; Page A01

Second of three articles

LOMBARD, Ill.

A thick, humid blanket of midsummer heat settled over the central Midwest. Only 9 in the morning and already it was closing in on 90 degrees. At the electricity-grid control center west of Chicago, engineer Pat Shanahan watched the numbers on his computer screen soar as millions of air conditioners cranked up.

By 9:24, the rising demand threatened to overload one of the region's main conduits of electricity -- a towering high-voltage line running into Des Moines from the east. On this day, it was funneling power from as far away as Arkansas, Illinois and Minnesota to customers west and south of Iowa.

Shanahan moved quickly, halting delivery of 395 megawatts of power trying to get through the line -- enough to light a small city. Utilities in Des Moines and elsewhere in the heat belt had to scramble for more expensive sources of electricity closer to home.

Decisions such as the one made by Shanahan that July morning are no longer unusual. The people who manage the nation's 200,000 miles of transmission lines are increasingly forced to block delivery of power moving through the wires -- because the grid was not built to handle the new kind of electricity system emerging across America.

This freewheeling, market-driven system presumes that power can be sent immediately over long distances, from places with a temporary surplus to places with a temporary deficit. But the aging grid is full of bottlenecks that many experts say threaten the reliability of the power supply in times of shortages and emergencies. More important, say federal regulators say, transmission congestion is undermining the benefits of deregulation by denying consumers access to cheaper electricity from distant suppliers.

"Three years ago, we didn't have these problems," said Mark Fidrych, chairman of a national group of power-line coordinators. The grid, he said, is "being used in a way that it was not designed to be used."

When the Flow Won't Go

Until recently, significant transfers of electric power between regions were much less common. About 20,000 such transactions occurred a year, mostly short-range swaps between neighboring utilities.

Now, 20,000 transfers may occur on a single day of heavy traffic, said Michehl R. Gent, president of the North American Electric Reliability Council (NERC), an industry group responsible for the national grid's performance. And the transfers typically involve longer distances than ever.

The bigger power flows have created chronic hot spots of congestion. A key bottleneck in central California kept surplus power in the south from reaching northern cities hit by rotating blackouts last winter. Lines bringing power to New York City from the north and west are regularly at full capacity. A year ago, a brief power shortage there led to a spike in prices that added an estimated $100 million to ratepayers' bills.

Heavy traffic frequently overwhelms the primary transmission line linking Minneapolis and Chicago through central Wisconsin. Jose Delgado, president of American Transmission Co., the line's operator, said that if the line failed now, as happened once in 1998, the sudden disruption to the surrounding multi-state network would be very hard to control.

Last summer, an unprecedented flow of electricity moving from the Great Lakes region into the Deep South jammed up trying to get through the Midwest and the Tennessee Valley Authority's power lines. "At times it exceeded our safety limits," said Len Januzik, Lombard's director of engineering.

The enormous increase in the flow of electricity has heightened the risk of a far-reaching power blackout triggered by an unexpected loss of a major generating plant along a crowded transmission line, said David Cook, NERC's general counsel. The problem is exacerbated by some energy companies that are taking more chances in overloading the system to boost profits, he contended. "The question is not whether but when the next major failure of the grid will occur," Cook said. Some analysts liken the managers of the grid to air-traffic controllers when bad weather hits a crowded airport. At the control center in Lombard, which is run by a consortium of Midwestern utilities, Shanahan and other operators make decisions on an hour-by-hour schedule, needing to move quickly to prevent overloads whenever the demand threatens to surge beyond the capacity of the wires. Last summer, the number of "temporary loading relief" orders issued at Lombard and other control centers to block power shipments was more than three times the 1999 figure.

Karl Stahlkopf, vice president of EPRI, a Palo Alto, Calif., energy research and consulting firm that specializes in the reliability of transmission lines, said the systems and their overseers are seriously stressed. "The people are not equipped to handle it," he said.

Grid managers don't go that far, but they do not dispute that as the strains on the system have grown, so have the risks of major outages. Richard Bulley, the Lombard center's executive director, said, "We certainly are operating closer to the edge, and closer than I feel comfortable with."

New Power, Few New Lines

The remaking of the country's electric system began with enactment of federal legislation in 1992. Before then, power supply was essentially a local service provided by state-regulated utility monopolies and smaller municipal or cooperative power suppliers.

The 1992 law authorized the creation of new energy marketing companies to compete with utilities. To give competition a chance, Congress and the Federal Energy Regulatory Commission (FERC) ordered that utilities controlling transmission lines also move competitors' electricity -- without discriminatory interference.

About half the states have taken an additional step, opening the retail sale of electricity to competing suppliers. California's failed experiment with deregulation is the best-known case, but Maryland, Virginia and the District are among the jurisdictions that have authorized retail competition.

In theory, generators would build new, efficient power plants, competing to sell power at cheaper prices. Utilities and marketers would scour the country for the best power bargains, and the consumer would be the winner.

In fact, the new policies have led to a sudden spurt in power-plant construction nationwide. The plants will help prevent blackouts. But they also create more congestion because increasingly the new plants are built to ship power to customers who are most willing to pay for it, rather than serving communities nearest to them.

Many new projects, for example, are being located along the Gulf Coast to be near supplies of natural gas that is burned to produce electricity. Since they will generate more power than their region requires, they will try to push the surplus north to major East Coast and Great Lakes markets.

But, as Kevin A. Kelly, a FERC policy director, pointed out, "there really isn't enough transmission capacity to move the power up there."

The nation's network of power lines is growing by less than 1 percent a year, NERC said. One reason is that utilities whose transmission lines are crowded with long-distance power shipments have relatively little to gain by creating more capacity for competitors to use.

When a Louisiana generator trying to ship power to Chicago runs into a bottleneck in the Tennessee Valley Authority's system, for example, the fix would seem to be for TVA to build more lines. But the TVA doesn't share the payments that the Chicago customers make to the Louisiana power company. It is just the conduit of that deal.

"The utilities ask, 'What's my incentive to invest in transmission?' " Stahlkopf said. "There isn't any. . . . It brings more competition to the market."

Proposals for new power lines also run into intense "not in my back yard" opposition and uncertainty about the outcome of regulatory changes. Some major interstate transmission projects have been blocked by state officials who don't need the power and don't want the towers on their turf. A case in point was the plan to bring badly needed electricity from New England to New York City over Long Island Sound. It was vetoed this year by Connecticut.

FERC's commissioners say that congestion problems require the formation of independent regional transmission organizations (RTOs) with the clout to plan and carry out expansion and interconnection of the grid in the most efficient way, without favoring any particular power supplier.

But the campaign for strong regional authorities is proceeding slowly, largely because major utilities that generate power want to maintain their influence over transmission decisions even after the new RTOs are established, some analysts say. The more influence a utility has over transmission in its market, the more influence it can have over power prices and profits.

"The transmission owners are jockeying with each other to set up an RTO to benefit their shareholders," said Eric Hirst, a consultant who has analyzed transmission issues for the Edison Electric Institute, a Washington-based lobbying arm for the power industry.

The Bush administration expects to offer a wide-ranging legislative proposal next month to strengthen the grid, and senior officials believe a consensus can be worked out with the Senate Democrats and House Republicans who lead energy committees.

Under the administration's plan, Congress would endorse FERC's regional grid strategy. FERC could decide where to locate major interstate transmission lines in cooperation with state regulators, but it would not have absolute control over all transmission siting.

Path of Least Resistance

Without an overhaul of the grid, its operators must face uncertainty each day, not only because of the shifting politics and economics of electricity but also because of the laws of physics. They say they have grown less confident of their ability to predict where destabilizing power flows are going to occur.

When utilities buy power from distant suppliers, they must secure a route for the shipment using a central computer system administered by NERC that shows which transmission routes are available.

For example, Entergy, the big New Orleans-based energy company, found power at an attractive price in the Chicago area July 9. It lined up a serpentine delivery route over power lines in Illinois, down into Appalachia and the Tennessee Valley and finally to its system along the Mississippi River. Entergy's transmission charges were based on that routing. In most cases, the more congested power lines become, the higher the price of moving power.

But grid operators say they have no way of knowing how much of Entergy's system actually followed that path. Electricity speeds through whatever power lines are available at the moment, seeking the path of least electrical resistance.

Imagine, engineers say, scores of cities connected by a spider web of giant water hoses. When a power plant in Chicago dispatches a new supply of power into the grid, it's as if a high-pressure hose started pumping more water into the hose network. The flow could go south via Missouri or loop around through Ohio and Kentucky, depending on which hoses had the most room.

"So far this year, we're seeing it in every direction," said Dale Landgren, vice president of Wisconsin's American Transmission Co. "It's no longer very predictable on any given day which way the power is going to be flowing."

The unpredictable nature of the flow increases the likelihood of bottlenecks. Congestion, in turn, tempts some utilities to cut corners on safety procedures, risking overloads on power lines to avoid losing a transmission deal. Although most utilities and merchant generators promise to live by the rules issued by NERC, the industry's watchdog, it is an honor system without enforceable sanctions.

"Last summer, there were a number of instances where operators allowed [transmission] facilities to remain loaded above their security limits for extended periods of time, placing the grid at prolonged risk of major failure," NERC's Cook told a Senate committee recently. Those utilities "made the economic judgment that it is less costly to them to violate the rules than to follow them."

In one incident, rule-breaking led to a major outage, according to NERC officials. Early on the morning of June 25, 1998, a pair of severe lightning strikes 44 minutes apart knocked out two major electric power lines in Minnesota and Wisconsin. The strikes triggered uncontrollable power surges that tripped circuit breakers and shut down power plants throughout the western Great Lakes region and in neighboring parts of Canada. In all, 150,000 customers were blacked out, and service was not fully restored for 19 hours.

Grid security procedures required Northern States Power, a Minneapolis-based energy company, to intervene immediately after the first lightning strike to safeguard the network against a second major incident by reducing power shipments over the Wisconsin line, NERC said. Northern States said it followed the rules. NERC insisted it didn't, leaving the network vulnerable to the second strike.

Federal regulators say the grid's increasing importance calls for regulations with teeth. The Bush administration's plan would, for the first time, impose penalties on power companies that deliberately overload lines to boost profits and on transmission-line owners who obstruct competitors' power deliveries.

But even when the rules are being followed, the grid can fail consumers when it is needed most. During another heat siege early this summer, two of the largest power plants serving Cedar Rapids in eastern Iowa went off-line because of equipment breakdowns. Alliant Energy Corp., the area's utility, had to import power through Illinois to keep its customers' lights on. But a key circuit delivering the power became overloaded and grid managers stopped the shipments. Alliant had to cut off power by prearrangement with a number of businesses and schools, delaying some graduation ceremonies.

"To some extent, it was bad timing, but it's a precursor of problems to come as demand continues to grow," said Alliant official Dan Presser. "If everything is working, we're fine. But when something goes wrong, our maneuverability is being compromised. It points out how fragile the system is."

© 2001 The Washington Post Company

-- Swissrose (cellier3@mindspring.com), August 22, 2001

Answers

Two statements in this article "jump out," as evidence that Y2K bugs in the embedded systems are at least part of the reason for the "new" bottlenecks in the grid:

"Three years ago, we didn't have these problems," said Mark Fidrych, chairman of a national group of power-line coordinators.

Last summer, the number of "temporary loading relief" orders issued at Lombard and other control centers to block power shipments was more than three times the 1999 figure.

-- Robert Riggs (rxr.999@worldnet.att.net), August 23, 2001.


It does not look like an embedded problem to me. Its a capacity problem. Demand is increasing and NIMBY prevents more lines being added.

-- John Littmann (johntl@mtn.org), August 23, 2001.

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