Outage Shines Light on Need for Smarter System
Outdated safety technology that automatically cuts off electric transmission lines and generating plants when things go awry may inadvertently have helped spread this month’s Northeast blackout to 50 million people in two countries, industry experts say.
While the U.S. electric grid is no Third World hodgepodge of sparking wires and rusty towers, it has yet to fully enter the age of advanced computing.
Technology widely used in Japan can instantly reroute power, helping to dissipate potentially dangerous fluctuations and preventing critical equipment from burning out without necessarily having to go offline. The safeguards in the U.S. don’t provide as many options in a crisis.
“We have 1950s technology -- essentially a mechanical system, a dumb system,” said Clark W. Gellings, a vice president of the Electric Power Research Institute, a Palo Alto consortium. Gellings is an advocate of intelligent control systems broadly known as “power electronics.”
Intelligent control systems might not have been able to keep the lights on in every city, but they certainly would have localized the blackout, Gellings said.
“We could have ended up with perhaps some parts of Cincinnati without power, but the rest of the Northeast staying on,” he said, referring to a type of power electronics known as Flexible Alternating Current Transmission Systems, or FACTS.
About the size of a small warehouse, with innards that look like components of a giant transistor radio, the units use computers to monitor and adjust the transmission system.
Under normal conditions, they can enable more power to flow on existing lines. In an emergency, they can immediately redirect flows.
Had several FACTS installations been in place Aug. 14 around Lake Erie, they might have headed off the sudden reversal in power flows that triggered cascading outages throughout the Northeast, several industry and academic experts said.
FACTS is only one of a range of options that could improve the resilience of the U.S. grid. Others include building more transmission lines, placing generating units closer to where electricity is most needed, and encouraging people to conserve.
Yet investment in technology and other upgrades has been stymied partly because of the nation’s incomplete and sometimes chaotic experiments with electricity deregulation.
In a deregulated market, utilities face giving up control of their transmission systems so that all generators can have access to customers. If a competitor stands a chance to reap the benefit, that can reduce incentives to invest.
“Back when utilities were regional or municipal monopolies, they knew they had to plan to serve their load [demand],” said Texas A&M; University professor B. Don Russell, a past president of the Power Engineering Society. “With deregulation, those companies have been broken up. The groups responsible for generation and those responsible for transmission are no longer the same. They are now into optimization of their own circumstances.”
Such a fragmented outlook doesn’t bode well for the future of the complex electric grid.
“We are talking about huge amounts of power,” said Peter W. Sauer, a senior professor of electrical engineering at the University of Illinois. “Power is big ... it’s as powerful as the Bomb. Trying to control that power is not easy.”
Electricity moves at about the speed of light, so when a serious problem occurs, humans aren’t able to react quickly enough to head it off.
For that reason, engineers have designed automatic safeguards that cut off key parts of the system in an emergency, much like home circuit breakers or fuses.
On the power grid, thousands of sensors called relays constantly monitor conditions. If a relay senses a problem, it signals super-sized circuit breakers that separate generating plants and other components from the rest of the network.
Although the power went out Aug. 14, the safeguards worked to prevent damage that could have made much of the U.S. power system as dysfunctional as Baghdad’s.
The problem with current safeguards, Sauer said, is that they are nearsighted.
Although the grid is functioning as an integrated whole, key safety devices are responding to localized conditions.
“They don’t see the big picture -- what would be the best thing to do to isolate the problem,” Sauer said.
That’s where FACTS technology can help, said Gregory Reed, a vice president of Mitsubishi Electric Power Products, one of several manufacturers of the equipment.
“What FACTS controllers do is build intelligence into the grid,” Reed said. They monitor a broader range of the network and are able to take more sophisticated corrective action, such as redirecting flows of power to avoid triggering a shutdown.
“As lines get overloaded, these devices act as electronic valves, redirecting power very rapidly,” Reed said.
Ranging from about $10 million to $30 million apiece, only a few dozen FACTS units are in place in the U.S., installed mainly to stabilize stubborn local problems.
But FACTS could also be used to help maintain the overall health of the electric grid, Reed said. They could make for a more stable network that is also capable of handling more power.
The investigation of the outages is focusing on finding the initial cause, most likely a combination of equipment failure and human error.
But the state of the grid may turn out to be the more important question, said M. Granger Morgan, head of the engineering and public policy department at Carnegie Mellon University in Pittsburgh. And the debate is likely to be far-ranging.
“This was not some ‘perfect storm,’ ” Morgan said. “Lots of combinations of problems could cause difficulties of a similar magnitude.... Things are going to stay that way until we make some fairly substantial investments to upgrade capacity, improve information flow and coordination, and get some new and smarter technology in there.”
The design of the grid should be reevaluated, Morgan said.
“There are two philosophies of intelligent control,” he said. “One says there is someone looking at everything and controlling it all. Another says put a lot of the intelligence out in the system. Nobody is in charge of the Internet; it’s a network of intelligent switches. Perhaps the power system needs to move much more in the direction of distributed control.”
Similarly, some experts favor moving more generation plants closer to areas that heavily consume power, so electricity would not have to flow as far on the transmission system. Some local and environmental objections might be overcome by keeping the plants small.
“We need to do more than just build transmission,” said Mark Bernstein, an energy policy analyst at the Rand Corp. “We need to site small-scale generation around where you have the demand. We need to reduce peak-load demand. We need a portfolio of solutions.”
Although President Bush and other officials have pointed to the energy bill pending in Congress as the cure for another massive blackout, experts say it is more like a first step.
The legislation won’t guarantee the necessary investment of possibly billions of dollars, and it doesn’t resolve the debate about control of the grid.
