What+is+an+outage+for+a+nuclear+facility?



** Cooper Nuclear Station ** ** RE27 Refueling Outage Information **

U.S. nuclear reactors shut down once every 18 to 24 months to refuel approximately one-third of the reactor. In the 1980s and early '90s the average refueling outage lasted about three months. Over the past decade, refueling outage durations have improved substantially. Now a typical refueling outage lasts one month.


 * Shortest **

PWR: Braidwood 2; 15 days; 2003

BWR: Browns Ferry 3; 15 days; 2002


 * Average / Median **

2006 industry average: 39 days; median: 37 days

1990 industry average: 104 days; median: 85 days

CNS is on an 18 month refueling cycle and following this outage will be prepared to extend to 24 months between refueling outages. It’s not just new fuel that happens during an outage. When the plant is shut down it allows access to thousands of components that can’t be worked on while the plant is running. This is primarily due to the high levels of radiation in some areas while running at power.

This outage will be labeled RE27 which means it’s the 27th refueling outage for CNS since it went commercial in 1974. The number of workers will more than double during the outage which means there will be over 1,700 people on-site. Over 1,770 work orders will be completed to correct equipment conditions and to perform preventative maintenance on equipment. In addition, several large modifications are planned for this outage including installation of 4 new Main Transformers, 2 new Service Water Strainers, new Main Steam line pipe supports and modifications to many safety valves.

Keys to a successful outage include Safety, Radiation Dose, Dollars spent & Duration. CNS goals for RE27 include:

OSHA Recordable Accidents: 0

Radiation Dose: <125 Rem

Dollars : < $40.3 Million

Duration: </= 27 Days

Another important indicator of a successful outage is how long we operate following an outage without equipment problems that take us back off line. In order to achieve a good post-outage run you have to work on the right equipment and with quality craftsmanship. Barring any problems CNS will have gone over 516 days of continuous run when we shut down for refueling on Oct 13th. The previous record was 484 days and that was just last cycle. For the second cycle in a row, we have raised the bar and established new levels of excellence at CNS. It’s obvious we are working on the right things and with excellent craftsmanship.