Spectral lines: Blackout prevention

Several factors helped drive the metropolitan New York area into total blackout on a hot summer night in July. The blackout was reminiscent of the Northeast Blackout of 1965 — although not as widespread, it lasted longer. Investigative teams, including Con Ed´s own, have since quickly and accurately analyzed the 53-minute sequence that resulted in complete isolation and shutdown of the Con Ed system. There were no real surprises, except, perhaps, the lightning stroke that started it all by tripping, simultaneously, two circuit breakers on adjacent power lines between Buchanan and Millwood, in Westchester County. Following this, certain equipment did not operate in a satisfactory manner, but in each case the cause or probable cause was diagnosed subsequent to the outage. In any event, these failures to function optimally or at all were in a fail-safe direction, so that equipment was safeguarded. Indeed, one of the criticisms resulting from the investigation relates to the possibility of overly conservative settings and/or inappropriate configurations that voided generating capacity prematurely. Further, it is generally conceded by the investigators that the Con Ed system itself is vulnerable to mishaps because its ties to the outside world are marginal when compared to that of other systems. This situation was compounded at the time of the blackout by an out-of-service intertie between New Jersey and Brooklyn. Finally, the communications among control centers left much to be desired. Much of the information transmitted during the critical period was by informal voice (telephone) communication, some of it ambiguous, unclear, or incomplete.