Utilities

Power Outages

Classed by duration, there are three kinds of power outages: dropouts, which are almost instantaneous (when the power flickers), brownouts (when the voltage drops, but power is not cut off), and blackouts (when the power is cut completely). During storm conditions and while the distribution system is being repaired, dropouts can anticipate a blackout. During widespread power outages, there will often be areas suffering from brownout in addition to the blacked-out parts of the grid. Brownouts reduce the amount of power going to the devices connected to the grid; thus, incandescent lights will dim, electric heaters will cool off, and old cathode-ray-tube televisions will experience screen image fluctuations as the frequency rates of its circuits slow down. Some devices will simply fail to work, needing more voltage to operate than they can draw from the grid.

An increasing concern is the possibility of massive power outages caused even without such external damage to the physical infrastructure. The 2003 northeast blackout was the most widespread blackout in North American history, impacting 45 million people in eight states and a further 10 million people in Ontario. Terrorism was at first suspected as a possible cause, but was ruled out by the evening, some eight hours after the outage began. Most areas regained power by the end of the day; Ontario and New York City were the last to be fully restored, in the following two days. It took longer than that to determine the outage's cause. Because electric power is difficult to store, the demand on a power grid must be matched by its supply and its transmission capacity. Significant overloads can damage a power line, while either overloads or underloads can damage a generator, so grids are built to turn elements off to prevent this. In some cases, this can result in cascading failures, when the load is shifted from element to element, overloading each in turn like falling dominos. Cascading failures had resulted in the 1965 northeast blackout, in which 25 million people were effected over 12 hours, when utility workers miscalibrated a safety relay. In the 2003 blackout, the cause was twofold. To begin with, the American power grid has been widely criticized as a relic, prone to trauma and overloading. New Mexico governor and former Secretary of Energy Bill Richardson have both characterized the United States as “the superpower with a third-world electricity [Page 757]grid.” As early as the late 1970s, engineers and commentators had pointed to the infrastructural vulnerability of the American grid, and the ease with which it could fail. This weakness of the grid is what resulted in a moderate problem becoming a disastrous one. The factor that was eventually blamed for setting off the outage was the failure of the FirstEnergy Corporation in Ohio to sufficiently trim the trees in its service area. High-voltage lines in a rural area came into contact with overgrown trees, which when combined with a nearby generator going offline during a high-demand period, resulted in over 100 power plants going offline during massive cascading failures of an unprecedented scale.

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