Environmental Engineering Reference
In-Depth Information
link very large generating units, are highly centralized, and are vulnerable to outages cause by
weather, seismic disturbances, and human actions. Local distribution networks are often disrupted
by automobile accidents involving collisions between motor vehicles and power poles, generally
affecting small geographic areas. However, the larger regional high-voltage bulk electric power
networks are also vulnerable to local disruptions involving equipment failure, human error, or
intentional acts of sabotage. Unfortunately, transmission networks are so vast, complicated, and
fragile that local disruptions may have multistate regional ramifications.
The desirability of increased interdependence that accompanies interconnection of facilities
was dramatically put in question by the Northeast power failure of November 9, 1965 (Hamilton
1979, 128), when an incorrect setting on a backup protective relay disconnected a high-voltage
230kV transmission line in Ontario, Canada, triggering a series of events on the interconnected
transmission grid that resulted in loss of electric service to about 30 million customers over 80,000
square miles in six northeastern states (New York, Connecticut, Massachusetts, Rhode Island,
Pennsylvania, and New Jersey) and substantial portions of Ontario for up to thirteen hours (USFPC
1967). On that date the United States found out how vulnerable it is to large-scale disruptions of
the electric transmission system. Brief, local disruptions had occurred frequently in the past, but
this was the first time several states were blacked out for many hours, and the effect on the industry
was profound. An extensive report on this first major regional blackout published by the Federal
Power Commission (FPC) in 1967 suggested ways of increasing the reliability of the nation's
transmission systems. Shortly thereafter the FPC called on the electric power industry to establish
national and regional coordinating bodies (Hamilton 1980, 46). The industry responded by setting
up nine regional and one national coordinating council, the National Electric Reliability Council,
“which subsequently dealt primarily with transmission reliability and not with the economic
aspects of coordination” (Breyer and MacAvoy 1974, 112). “Reliability” in this context meant
maintaining the capability to deliver electricity to consumers without significant or widespread
interruption (Hamilton 1980, 42).
The council was created in 1968 as a voluntary association of nine regional reliability councils
that together blanketed the United States, most of Canada, and small portions of northern Mexico;
it was incorporated in 1975 as a not-for-profit corporation in New Jersey (National Electric Reli-
ability Council 1976, 2). With the vivid and frightening memory of the Northeastern blackout still
fresh, the emphasis at that time was on
reliability
of the transmission network in order to avoid
future power blackouts. However, emphasis soon shifted to the
adequacy
of bulk power supply
(National Electric Reliability Council 1976, 3) to meet demand for electric power.
Each of the regional councils established a planning coordination committee to accumulate
data relevant to the interconnected systems in their regions, to perform regional studies, and to
formulate reports and recommendations for their respective councils. These committees studied
the performance of interconnected systems within their regions and recommended system design
criteria for adding new generating and transmission capacity to interconnected systems. They
compiled and shared information pertaining to planned generator additions and performed regional
studies to assess actual and potential performance problems of the growing interconnected grids.
This oversight involved maintenance of regional data banks and small technical staffs and use of
computer simulations of existing and planned load-flows of electricity within regional intercon-
nected systems under normal and disturbed conditions.
Although it continued to be the responsibility of each individual utility to plan facilities and
resources to meet its future load demands, regional planning coordination committees were involved
in early stages of planning new facilities or increases in generating capacity of existing facilities,
well before cost analysis of such plans had begun. Based on technical consideration of additional
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