Nuclear Utility User Group

The 15th annual gathering of the ETAP Nuclear Utility User Group (NUUG) took place June 16-19, 2015 in Irvine, CA, where 53 members from 25 companies and 22 nuclear plants shared presentations on nuclear plant electrical power system analysis.

 The ETAP NUUG has become the largest group in the U.S. that regularly meets to discuss nuclear plant power system analysis. “Recent events in the nuclear industry have emphasized the important role a power system analysis can play in determining the best solution to various electrical system failures”, explained ETAP NUUG Chairman, Mark Bowman of Tennessee Valley Authority (TVA). “Our conference attendance has increased in recent years,” noted ETAP NUUG Technical Chairman, Paul Colaianni of Duke Energy, “This is partly due to the nuclear power industry’s strong safety culture, which fosters the need for our members to work together to increase overall plant safety margins by continually improving our power system modeling and analysis techniques.”

The ETAP Nuclear Utility Users Group was originally formed in 1999 by TVA, Duke Energy, Virginia Power (Dominion), and Operation Technology, Inc. (OTI). The group meets annually to discuss application and development of ETAP software with respect to the nuclear power industry. The purpose of the group is to provide a forum for its members to:

• Share operating experience (OE) related to ETAP-based power system analysis
• Share techniques and philosophies used in analyzing nuclear power plant electrical power systems
• Encourage best practices for electric power system model development and maintenance
• Address improvement of the ETAP software as a group
• Encourage the exchange of member experiences and ideas

Highlights from this year’s agenda include:

• Keynote address by the Nuclear Energy Institute (NEI)
• New features of ETAP 14 (new release)
• Review of site-specific ETAP power system models (5 nuclear plants)
• ETAP model control procedures
• Recent power system analysis issues in NRC inspections
• Open-phase fault analyses
• Motor operation with unbalanced voltages
• Degraded voltage analysis
• Fast-bus transfer analysis
• Motor operated valve analysis with voltage and frequency variations
• AC/DC Arc Flash analysis
• DC system modeling for ‘beyond design basis’ events
• ETAP Symposium, including review of proposed new features

Also highlighted at this meeting was an initiative to focus on best practices for electric power system models. "The starting point of any analysis is the development of the electrical system model. A quality analysis cannot be performed without technically accurate system and component models. Once developed, complexity and risks are introduced when the model is not updated routinely to eliminate backlogs. The most common factor contributing to backlogs is inadequate numbers of trained personnel dedicated to the task. These two factors, quality development and adequate maintenance, are our next focus.", explained ETAP NUUG Technical Chair, Paul Colaianni of Duke Energy.

ETAP NUUG 2015 Agenda