Saturday, July 9, 2016
12:36 p.m.
For immediate release:
Total power restoration to require another 24 to 48 hours
JOHNSON CITY -- Johnson City Power Board officials indicate total power restoration will
require another 24 to 48 hours due to the extensive system damage caused by Friday evening
storms.
Straight line winds above 70 mph snapped dozens of power poles, and downed dozens of
power lines as trees fell throughout the Johnson City Power Board system.
At the height of the storm, at least 52,000, or 67.5 percent of the system's customers,
temporarily lost power. By 2:30 a.m. Saturday, outages were down to 8,000 and by 10 a.m. less
than 4,000 were without power.
Repair contractors have responded and more are on their way to Washington County to help
complete repairs, and neighboring systems are lending crews as they can make available.
Persons using medical equipment requiring charging should seek other accommodations as the
system cannot guarantee restoration times at this point due to the extensive system damage.
In addition, JCPB would like to remind customers to stay away from fallen power lines and do
not attempt to remove fallen trees entangled in power lines. Further, if a customer's service is
damaged, which is the span of wire running from the closest power pole to the house itself,
then the law requires any repairs be inspected and approved before service can be restored.
A quick primer on how your power will get restored:
When a storm event hits, debris may lodge on a power line. This will automatically activate a recloser system that attempts to jolt the debris off the line. This is also the cause of the "flicker of
lights" before the power kicks off completely.
After three actions, if the fault is still apparent, the breaker in the substation will “open.” This is
identical to having a short or other fault in your home system, which kicks the breaker open.
This system operates this way to protect the major equipment, transformers and other large
equipment that require a lot of time to replace.
When you start to repair an electric system, you start at the substations, just like you would
start at the breaker box in your home. Line crews ride the feeder power lines and remove any
debris or repair any damage that would cause the breaker to operate (open). When you have
infrastructure destroyed, like power poles and downed lines, repairs take time. By following
this process, you more quickly restore the largest number of customers, although small groups
or individual customers will remain without power.
Similarly, at home, you would just unplug that old hair dryer that caused the breaker to open
on your breaker panel, and then re-close the breaker, restoring power to any undamaged
circuits.
When you get to the neighborhood level, repairs become slower. With the widespread damage
evident from this storm, you have hundreds or even thousands of minor faults that must be
repaired. When many people think a transformer “blows”, it is actually a cut-out, or fuse, that
again is designed to protect the most difficult to replace infrastructure.
Each neighborhood fuse serves one or two households up to 100 or more, and these must be
replaced, in addition to repairing any infrastructure damage such as downed power lines and
broken poles. This is also why you may have only one house without power while all their
neighbors are supplied.
The staff of the Johnson City Power Board work hard daily to provide the highest possible
reliability. This particular storm event and system level damage is very rare, and when such an
event occurs, it takes a considerable amount of time to repair.