skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Evaluation of Loss of Offsite Power Events at Nuclear Power Plants: 1980 - 1996

Abstract

It is recognized that the availability of AC power to commercial nuclear power plants is essential for safe operations and accident recovery. A loss of offsite power (LOSP) event, therefore, is considered an important contributor to total risk at nuclear power plants. In 1988, the U. S. Nuclear Regulatory Commission published NUREG-1032 to report on an evaluation of the risk from actual LOSP events that had occurred at nuclear power plants within the United States up through 1985. This paper summarizes a similar study, whose primary objective was to update the LOSP model parameters, frequency and recovery time, using power plant event data from 1980-1996, published as NUREG/CR-5496 in 1998. An additional objective of the study is to re-examine the engineering insights concerning LOSP events.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID
Sponsoring Org.:
USDOE
OSTI Identifier:
7708
Report Number(s):
INEEL/CON-99-00471
ON: DE00007708
DOE Contract Number:
AC07-94ID13223
Resource Type:
Conference
Resource Relation:
Conference: Probabilistic Safety Assessment, 1999, Washington, DC, 08/01/99 - 08/01/99
Country of Publication:
United States
Language:
English
Subject:
21 NUCLEAR POWER REACTORS AND ASSOCIATED PLANTS; 22 NUCLEAR REACTOR TECHNOLOGY; 24 POWER TRANSMISSION AND DISTRIBUTION; Nuclear Power Plants; Power Losses; Risk Assessment

Citation Formats

C. L. Atwood, D. A. Prawdzik, D. L. Kelly, F. M. Marshall, and J. W. Stetkar. Evaluation of Loss of Offsite Power Events at Nuclear Power Plants: 1980 - 1996. United States: N. p., 1999. Web.
C. L. Atwood, D. A. Prawdzik, D. L. Kelly, F. M. Marshall, & J. W. Stetkar. Evaluation of Loss of Offsite Power Events at Nuclear Power Plants: 1980 - 1996. United States.
C. L. Atwood, D. A. Prawdzik, D. L. Kelly, F. M. Marshall, and J. W. Stetkar. 1999. "Evaluation of Loss of Offsite Power Events at Nuclear Power Plants: 1980 - 1996". United States. doi:.
@article{osti_7708,
title = {Evaluation of Loss of Offsite Power Events at Nuclear Power Plants: 1980 - 1996},
author = {C. L. Atwood and D. A. Prawdzik and D. L. Kelly and F. M. Marshall and J. W. Stetkar},
abstractNote = {It is recognized that the availability of AC power to commercial nuclear power plants is essential for safe operations and accident recovery. A loss of offsite power (LOSP) event, therefore, is considered an important contributor to total risk at nuclear power plants. In 1988, the U. S. Nuclear Regulatory Commission published NUREG-1032 to report on an evaluation of the risk from actual LOSP events that had occurred at nuclear power plants within the United States up through 1985. This paper summarizes a similar study, whose primary objective was to update the LOSP model parameters, frequency and recovery time, using power plant event data from 1980-1996, published as NUREG/CR-5496 in 1998. An additional objective of the study is to re-examine the engineering insights concerning LOSP events.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1999,
month = 8
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • Significant differences have been identified in loss of offsite power (LOSP or LOOP) event description, category, duration, and applicability between the LOSP events used in NUREG/CR-6890 and ENS'LOSP packages, which were based on EPRI LOSP reports with plant-specific applicability analysis. Thus it is appropriate to reconcile the LOSP data listed in the subject NUREG and EPRI reports. A cross comparison showed that 62 LOSP events in NUREG/CR-6890 were not included in the EPRI reports while 4 events in EPRI reports were missing in the NUREG. Among the 62 events missing in EPRI reports, the majority were applicable to shutdown conditions,more » which could be classified as category IV events in EPRI reports if included. Detailed reviews of LERs concluded that some events did not result in total loss of offsite power. Some LOSP events were caused by subsequent component failures after a turbine/plant trip, which have been modeled specifically in most ENS plant PRA models. Moreover, ENS has modeled (or is going to model) the partial loss of offsite power events with partial LOSP initiating events. While the direct use of NUREG/CR-6890 results in SPAR models may be appropriate, its direct use in ENS' plant PRA models may not be appropriate because of modeling details in ENS' plant-specific PRA models. Therefore, this paper lists all the differences between the data in NUREG/CR-6890 and EPRI reports and evaluates the applicability of the LOSP events to ENS plant-specific PRA models. The refined LOSP data will characterize the LOSP risk in a more realistic fashion. (authors)« less
  • The US Nuclear Regulatory Commission (NRC) approved the adoption of cause codes for reportable events as a new performance indicator in March 1989. Corrective action data associated with the causes of events were to be compiled also. The corrective action data were considered as supplemental information but not identified formally as performance indicators. In support of NRC, the Nuclear Operations Analysis Center (NOAC) at the Oak Ridge National Laboratory has been routinely evaluating licensee event reports (LERs) for cause code and corrective action data since 1989. The compilation of corrective action data by NOAC represents the first systematic and comprehensivemore » compilation of this type of data.« less
  • An outline of the methodology was given of the collection of incident and failure data, the preparation of analysis sheets for human error events, the analysis and evaluation of each event of incident and failure, and the investigation of measures preventing human error. Subjects that need further development are outlined below: (1) Investigation of criteria for selection of human error events, (2) construction of a data base, (3) development of support system for analysis and evaluation method, and (4) investigation of measures preventing human errors.
  • 805The Nuclear Regulatory Commission (NRC) approved the adoption of cause codes for reportable events as a new performance indicator (PI) in March 1989. Corrective action data associated with the causes of events were to be compiled also. The corrective action data was considered as supplemental information but not identified formally as a performance indicator. In support of NRC, the Nuclear Operations Analysis Center (NOAC) at the Oak Ridge National Laboratory (ORNL) has been routinely evaluating licensee event reports (LERs) for cause code and corrective action data since 1989. The compilation of corrective action data by NOAC represents the first systematicmore » and comprehensive compilation of this type data. The thrust of analyzing the corrective action data was to identify areas where licensees allocated resources to solve problems and prevent the recurrence of personnel errors and equipment failures. The predominant areas of corrective action reported by licensees are to be evaluated by NRC to compare with NRC programs designed to improve plant performance. The set of corrective action codes used to correlate with individual cause codes and included in the analyses were: training, procedural modification, corrective discipline, management change, design modification, equipment replacement/adjustment, other, and unknown. 1 fig.« less