By Ariana Eunjung Cha
Washington Post Staff Writer
Tuesday, September 23, 2003; Page E01

We worry, complain and agonize about power when we don't have it -- when the lights go out and our appliances fail. But we hardly give it a thought when we have it.

Such is our all-encompassing dependence on what is arguably one of the largest and most complicated machines ever built by man: a national electrical grid made up of 3,000 utilities, 6,000 power plants and a maze of more than 160,000 miles of high-voltage transmission lines that crisscross the nation.

"Electricity is the lifeblood of today's economy, but it's like oxygen: You only miss it when it's not there," said Tom Kuhn, president of the Edison Electric Institute, a Washington-based lobbying group for power companies.

About 1.3 million people across the region felt this loss when the tropical storm that was Hurricane Isabel hit the area Thursday. The second of two powerful summer storms that wreaked havoc with the local power grid, Isabel tore through the most vulnerable link in the electricity supply chain: overhead power-transmission lines. Their vulnerability has been on gory display this week as people ponder just how reliable the electricity system is. The storms, coupled with the huge power outage that hit the Midwest, the Northeast and Canada last month, are focusing intense attention on the structure that underlies everyday actions, like flipping a switch and having the lights turn on.

By luck and design, the grid runs just fine most of the time. Robert Hinkel, a general manager for PJM Interconnection, a regional coordination center for utilities in seven states in the mid-Atlantic, monitors the grid from an underground control bunker in Valley Forge, Pa. When the system is working well, the numbers flash across his computer screen in a display of the beauty of a system in perfect mathematical balance.

At around 10 a.m. on a recent weekday before Isabel, the more than 700 generators that fall under Hinkel's organization's control area were producing 45,000 megawatts of power. At the same time, the 25 million people in the region were siphoning off almost 45,000 megawatts of power for light bulbs, computers, factories and other modern-day technical necessities.

This balance is no accident. Electricity is unique among commodities: It can't be packaged or stored like corn or oil. It has to be used as it is created. Too little, and there's a shortage in parts of the country and prices rise immediately. Too much, and the excess goes to waste, or worse, the extra power overwhelms transmission lines.

"Second by second, we always have to have generation equal to load minus some fairly small amount," Hinkel said.

If the equation grows too lopsided either way, Hinkel said, there's danger ahead. "You'd have a complete collapse of the system."

Maintaining this delicate equilibrium is no easy chore, given that the grid is hardly a monolithic entity. It is really made up of many parts. There exists no central authority to make decisions on how best to keep it running.

Instead, the grid is fractured into 142 independent "control centers," located in places such as Carmel, Ind. and Ann Arbor, Mich. These centers are the brains of the system and each day they monitor how much power is being produced and where. Some control centers direct the flow of power of multiple utilities in the same region; others oversee only a single utility.

In theory, the controllers all work toward the same goal -- keeping the lights on around the country. But in practice, things are much more complicated than that. Today's grid is as much a product of engineering principles as it is the often competing forces of supply and demand, competition, and government policies.

As recently as a generation ago, power was generated locally and it was used locally. Utilities were for the most part self-sufficient.

Then, as the country's population surged and the need for electricity grew with the exploding use of computers and other electrical gadgets, utilities began to connect their lines to each other as a way to increase reliability and efficiency. If one part of the grid went down, the theory went, other parts could make up for it.

The grid serving the United States eventually evolved into three large interconnected networks -- one for the eastern part of the country, one for the western part and one for Texas. The eastern and western grids emerged because that's where most of the big cities and population centers are located. Those two grids are connected ever so slightly along the Rocky Mountains by a handful of lines. Texas has its own grid for political reasons. Rich with natural resources, state officials and business leaders believed it would be cheaper and safer to run their own grid so they could avoid the additional rules of federal jurisdiction. It, too, is connected to the eastern and western grids but only minimally.

Last month's multiple-state blackout underscored the downside of the interconnections: interdependence. A failure in one part of the country could have devastating consequences hundreds of miles away. And Isabel showed last week that interconnected power systems don't help a whit when the transmission lines are torn down.

Deregulation of the energy market in 1992 created a surge of investment in new power plants as companies were allowed to charge market-based rates for power. But there was less incentive to invest in the grid's transmission lines as they were collectively owned and regulated. Many power expects now argue that the transmission lines, which are stuck with technology from the 1950s and '60s, are overwhelmed by the traffic required by today's digital economy and are too vulnerable to weather.

But even if the fragmented grids were more reliably connected together, their control operations have not been joined.

The rows of monitors in control centers display only what's going on inside one part of the country, but there's little data about what's going on elsewhere. It's as if a chorus line of dancers were blind. They can sense, by a movement of air or the sound of a brush of feet on the floors, whether the people next to them were in step, but as for the big picture, it's darkness. So if one person started kicking in the wrong direction, someone on the other end might not realize there's trouble until -- whoosh! -- she's knocked over.

"To operate well, control centers need to understand what's going on outside their system," said Luther Dow, director of power delivery and markets for the Electric Power Research Institute in Palo Alto, Calif. "And right now they have no way of knowing that."

This is especially important because electricity must be added into the grid in a very precise manner. According to the laws of physics, it must spin, jump and move in sync with the electricity already coursing through the grid.

Imagine that chorus line. Or an infinitely long tandem bicycle. For the group to achieve its goal, each individual must all be kicking in the same rhythm or peddling at the same rate. If even a single person slows down, speeds up, or trips, it can put a strain on the system, possibly sending the whole group tumbling.

Speculation about the cause of the massive 600-mile electrical blackout from Ohio to New Jersey last month so far has focused mostly on technology. Experts have said that the system needs more transmission lines, more sensors to catch fluctuations sooner, and better gates to control the flow of electricity from one place to another, but the failures of man may have played a role in the blackout.

There are no requirements to make sure everyone's technology is in sync. There are only voluntary standards. Managers of one segment don't demand additional power from another. They request it. And when they see something strange in their readings, no one forces them to ring the alarm bells to alert other control centers. They might, if they feel like it, put in a courtesy call.

The lack of central coordination centers complicates the already complicated problem of keeping the grid in balance. And, when a storm the size of Isabel leaves transmission lines in tatters, utilities can only request repair help from their neighboring systems.