Operators safely shut down the Unit 1 reactor at PPL's Susquehanna nuclear plant near Berwick, Pa. on Saturday (3/18) to begin the unit's eleventh planned refueling and inspection outage since the plant began commercial operation in 1983.
"Refueling and inspection outages are a crucial part of the operating cycle at Susquehanna," said Herbert D. Woodeshick, PPL's special assistant to the president for Susquehanna. "During this outage, the Unit 1 reactor will be partially replenished with uranium fuel, and equipment and reactor components will be systematically inspected, tested and refurbished," he added.
"We take the necessary time to maintain the peak operating condition of the Susquehanna plant," Woodeshick observed. "That translates into identifying potential problems of equipment reliability and addressing them long before they have a chance to become major difficulties affecting plant availability. The work done during a planned outage is a high form of systematic preventive maintenance."
Last March and April, Unit 2 at Susquehanna underwent a similar refueling and inspection outage. PPL's Nuclear Department schedules these outages for the spring because the demand for electricity is lower then, as compared with other times of the year. "The timing of this spring outage, aligned with ensuring reliability of equipment and availability of the plant's full capacity, will allow us to be ready for peak energy demand expected this summer," Woodeshick said.
About 35 percent of the unit's uranium fuel will be replaced during the outage, according to Woodeshick. This partial replenishing of the fuel will enable Unit 1 to operate continuously for 24 months before another refueling.
Some 2,300 wide-ranging work items-- involving the inspection, testing and adjustment of a wide variety of motors, pumps, pipes, valves, recorders, nozzles and other equipment-- will be completed while Unit 1 is shut down.
Among the specific projects to be accomplished are: the replacement of 256 fuel bundles; over one hundred different tests to confirm the leak-tight integrity of valves; replacement of a large water pump on a primary safety system; the overhaul of one of three low pressure turbines; and equipment modifications and testing of many other plant components.
Effective outages help ensure that Susquehanna safely generates the maximum amount of electricity, according to Woodeshick. "The outage is a controlled and well planned series of events supported by hundreds of dedicated and motivated employees and outside contractors," he said. "The four key ingredients of every job performed during this outage are safety, communication, quality and productivity."
Unit 1 has run for 248 consecutive days since an outage last summer to repair a valve controlling steam flow through one of the unit's four main steam lines. Since its last refueling and inspection outage two years ago, Unit 1 has generated about 15.7 billion kilowatt-hours of electricity. A kilowatt-hour is enough electricity to power a 100-watt light bulb for 10 hours. An average PPL residential customer uses about 10,000 kilowatt-hours a year.
Unit 1's operating capacity factor since the last refueling and inspection outage was 91 percent. Operating capacity factor, a measure of reliability, compares a unit's output to the amount of electricity it could generate if it ran continuously at full power.
The Susquehanna plant, jointly owned by PPL and Allegheny Electric Cooperative, Inc., is located about five miles northeast of Berwick, Pa., along Route 11.