Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: MONDAY, April 4, 1994 TAG: 9404080008
SECTION: EDITORIAL PAGE: A-9 EDITION: METRO
SOURCE: By JOSEPH H. VIPPERMAN
DATELINE: LENGTH: Long
Unfortunately, repeated severe weather over the past 12 months exposed many customers to unprecedented multiple extended outages. These raised questions I would like to address about our maintenance practices, underground line applications and restoration procedures.
Most actions have costs associated with them. Under standard regulatory practices, prudent construction, maintenance and operation costs generally are recoverable from customers. Our decision-making is, therefore, influenced by the trade-off of attempting to establish and maintain good service reliability and, at the same time, keep electric rates as low as practical.
To measure service reliability, we constantly monitor customer interruption data for our total customer base. Before the past 12 months, that reliability measure had been 99.977 percent, meaning customers, on average, experienced loss of service for two hours out of the total 8,760 hours in any given year. At the same time, rates paid by Appalachian customers are about 27 percent below the national average. An average Appalachian residential customer paid $2.08 a day for his or her electric service in 1993.
During 1993, we received $1.5 billion from all of our customers and paid $1.3 billion for operation and maintenance expense, including fuel, to produce and deliver service. The remaining $200 million went to pay interest and dividends on the $2.4 billion that has been borrowed and invested in physical facilities, such as power plants and lines.
With that background, let me turn to the questions raised:
Underground lines? Lower voltage lines and some higher lines can be placed underground, but at a higher cost and not without disadvantages. A 7,200-volt underground distribution line near a home costs three to five times as much as an equivalent overhead line and will be two to three times more costly to operate and maintain. A 69,000-volt line costs eight to 10 times as much for underground.
Naturally, an underground conductor is immune to interruptions caused by ice and falling trees. However, an underground conductor tends to deteriorate faster. More important, when the underground lines get in trouble, they are more difficult and time-consuming to repair. We face a trade-off - overhead lines lower costs to customers, but are exposed to more potential outages. Underground lines are more costly to install, are less exposed to weather-related outages, but require greater repair time.
Maintenance practices? While there are a variety of facilities that require various levels of maintenance, one item most often questioned during the severe weather was tree-trimming along rights of way. Our practice is to maintain a right of way wide enough to provide a reasonable balance between service reliability and cost, with the added factors in this case of aesthetics and environment. A wider right of way is more costly and has less eye appeal, but provides greater reliability. A narrower right of way is less costly to customers and causes fewer complaints about trimming practices, but sacrifices some degree of reliability.
Once right of way is obtained, our maintenance practice includes, where possible, the removal of trees within the right of way plus the removal of tall, dead trees outside the right-of-way that can, and do, fall when they become laden with ice and snow.
Service restoration? For isolated cases of trouble and during small-area storms, this is relatively simple. The affected customer reports a problem and a service crew is immediately dispatched to repair the damage.
Wide-area outages present a different situation. The most vexing problem for our customers is trying to contact us to report the outage. That is because of the vast number of customers without power relative to the number of phone lines available.
In the immediate Roanoke area, we have 30 phone lines into our facilities - more than enough to handle normal customer traffic. During a storm, all of these lines are pressed into customer service. Phones are staffed around the clock by employees from throughout the organization. When the customer reports only the essential information requested by the operator, the call can be handled and input into our computerized trouble system in about one minute or less, giving us the ability to handle approximately 2,000 Roanoke customers per hour.
In the most recent storm, Roanoke had almost 60,000 customers without power. If each customer called only once and relayed minimum information, it would require 30 hours to process the calls. Repeat calls and extended information delay the process.
As calls begin to come in, assessments begin regarding the best way to dispatch repair crews. Priority is given to hospitals and other emergency services if possible. Next, attention is directed to actions that will restore service to the greatest number of customers first.
For example, it is not unusual during a major storm to experience simultaneous outages on the main line feeder circuit, on the major tap lines feeding from the circuit and at individual customer locations at the ends of lines. The proper approach to service restoration in this situation is to repair the main feeder lines first, returning later to restore major taps, and finally individual services.
While this approach restores the greatest number of customers in the shortest time, it often leaves isolated customers within a neighborhood out of power.
Our normal work force is sized to handle regular work loads. During major outages, we begin immediately to call on contractors and neighboring utilities to supply labor to augment existing personnel. Under normal conditions, our Roanoke Division line crew and right-of-way-clearing work force totals 58 crews. During the last storm, we brought in more than 300 additional crews, expanding our work force to approximately 1,500 workers plus guides, dispatchers and other support personnel. Additional help was provided by volunteers, highway crews, restaurant and motel workers, emergency services personnel and others.
We regret the interruptions and inconvenience our customers experienced this winter. During the past 12 months, we estimate that storms have been seven times more damaging to Appalachian's electric facilities than in any other period in our history. We are continually attempting to modify and improve our approaches where practical, and I can assure you that the dedicated employees of Appalachian Power, most of whom experienced outages at their own homes, worked long and difficult hours to restore your electric service this past winter. I am proud of them and their accomplishments.
To our many customers who were courteous and helpful during this adversity; to the media who helped us communicate with our customers; to our suppliers, contractors, and other utilities who pulled out all stops to assist, we extend our heartfelt appreciation.
Joseph H. Vipperman is president of Appalachian Power Co.
by CNB