CHICAGO has a message for America: Beware the vunerability of the electric power system! Substation fires blacked out parts of Chicago July 28 and Aug. 5. An outraged Mayor Richard Daley Jr. plans an investigation.
He shouldn't be so surprised. In the context of the overall United States' - indeed North American - electric-power system, such blackouts are all too expectable. That's to say nothing of truly massive regional power failures.
Chicago's experience underscores the warning of a congressional Office of Technology Assessment (OTA) study. Released June 28, it has the apt title, ``Physical Vulnerability of Electric Systems to Natural Disasters and Sabotage.''
Hurricanes, earthquakes, and multiple lightning hits all can cause massive blackouts. Saboteurs blowing up unguarded substations could cripple large parts of the power system. Even vandals (or saboteurs) shooting out insulators that support power transmission cables can disrupt service.
Reviewing such threats, the study notes that utility companies have ``historically expended great efforts to ensure reliability,'' as the reasonably fast return of service after a local power failure repeatedly shows. But this resilience depends on having to cope with only one or two major failures at a time.
The OTA studies observe that ``only over the past few years have [utilities] started to take seriously the possibility of massive, simultaneous damage on multiple facilities. Awareness of the threat, however, has not yet led to the implementation of many measures to counter it. Few if any utilities plan their system and its operation to accommodate multiple, major failures, and key facilities are still unprotected.''
Chicago's blacked-out areas recovered quickly because they had suffered isolated events. Had the two substation fires occurred simultaneously, recovery could have been more difficult. Had there also been outages in the regional electrical grid, service could have been cut for days.
OTA says two trends enhance the vunerability. First, the United States' electrical-equipment manufacturing industry has declined. It would be hard to replace quickly the loss of more than a few large key components, such as substation transformers. Second, the power system's reserve margins of generating capacity have dropped as growth in normal electricity demand has exceeded construction of new power plants. The system, overall, has increasingly less ability to offset power loses in one region by importing electricity from an unaffected area.
In raising this warning, OTA sees no immediate crisis. But there is a growing long-term threat of crippling blackouts that it urges both the federal and local governments and the power industry to take seriously. It urges national coordinated action to fully analyze the problem and plan how to minimize the blackout threat in an economically acceptable manner. Total security is impossible. Many seemingly desirable measures, such as stockpiling more than a few large transformers, can be too costly. Also, as OTA points out, ``there is a clear national interest involved.'' Thus, it adds, ``Steps that may not be worthwhile for individual utilities could make sense from the national perspective.''
Government-industry partnership is needed to tackle this challenge. A presidential commission to develop a national electric-power security strategy would seem to be in order.