ML24275A002
| ML24275A002 | |
| Person / Time | |
|---|---|
| Issue date: | 09/30/2024 |
| From: | Gascot-Lozada R NRC/RES/DE/RGDB |
| To: | |
| References | |
| Download: ML24275A002 (1) | |
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Light Water Reactor Sustainability (LWRS) is a Department of Energy (DOE) program conducting research to develop technologies and other solutions to improve the economics and reliability, sustain the safety, and extend the operation of our nation's fleet of nuclear power plants (NPP). The NRC and the DOE has a Memorandum of Understanding (MOU) on Nuclear Innovation that allow the entities to share expertise and knowledge on advanced nuclear reactor technologies and nuclear energy innovation which extend to the area of light water reactor long-term operation and proposed modification for light water reactor sustainability.
LWRS Status Highlights September 2024 Material Research Pathway Program Mission Main Goal: understand and predict long-term behavior of materials in nuclear power plants Latest Report : Effect of thermal aging on microstructure and stress corrosion cracking behavior of an Alloy 152 1st layer butter weldment-The objective of this research is to understand the micro-structural changes occurring in high-Cr, Ni-based Alloy 152 weldments during long time exposure to the reactor operating temperatures, and the effect of these changes on the service performance. One area of particular concern is the potential for long range ordering (LRO), i.e.
formation of the intermetallic Ni2Cr phase under prolonged exposure to reactor temperatures and/or irradiation, which can increase strength, decrease ductility, and cause dimensional changes or lead to in-service embrittlement of components made with these alloys. Hence, this research focused on the microstructural evolution and the SCC response of Alloy 152 under accelerated thermal aging.
Locations where nanohardness profiles across 1st Layer of Alloy 152 weld butter/LAS interface were obtained: weld root and CT
Main Goal: enable plant efficiency improvements through a strategy for long-term modernization Latest Report : Mapping Data to Support Optimum Work Automation: The Socio-Technical-Organizational Modeling Process-The research presented a detailed analysis of a significant event at a commercial NPP and plotted the outcome of an analysis on the layered loop model to highlight the areas of weakness. The research team compared its results to that of the original root cause analysis and presented the differences in findings to a root cause expert from that utility to get critical feedback on the conclusions. Although different from the outcome of the analysis performed by the utility, the expert was intrigued with the out-come and expressed interest in helping to evaluate more test cases to further develop Socio-Technical -Organizational Modeling Process (STOMP).
Flexible Plant Operation &
Generation (FPOG) Pathway Page 2 Main Goal: enable diversification and increase revenue of light water reactors to produce non-electrical products Latest Reports:
Impacts of Extracting 30% of Reactor Power from a Pressurized Water Reactor-This report summarizes key impacts of 30% thermal power extraction on a generic Westing-house 4-loop PWR. In addition to a full details of the Performance Evaluation of Power System Efficiencies (PEPSE) modeling and impacts, including plant transients, hazards, and core reactivity impacts; reactor response to load rejection or other transient events would need to be assessed for acceptability through further core and plant response analysis. High-pressure/low-pressure turbine and moisture separator reheater performance is very similar to the performance under a 75% power case; this operating profile is expected to be maintainable for long durations. Condenser operating conditions are expected to continue to meet operation requirements while evacuation capacity will not be impacted.
Working fluid supply and return locations Plant Modernization Pathway Contrasting a root cause model (open loop) with a control theoretic model (closed loop).
Page 3 LWRS October Calendar Monthly Calls (link on the dates)
- FPOG Call-October 28, 2024-10:00-11:00 AM
- RISA Call-Power uprates core design and safety analyses October 15, 2024-1:00-2:00PM
- LWRS & ARSS Physical Security Meeting-October 23, 2024 - 2:00-4:00 PM
- LWRS Materials Research Stakeholder Meeting-November 13-15, 2024 Past Issues Prepared by: Ramón L. Gascot (RES/DE/RGPMB)
Main Goal: develop safety analysis methods and tools to optimize the safety, reliability, and economics of nuclear power plants Physical Security Pathway Main Goal: develop technologies and technical bases to optimize physical security Latest Report: No report for this issue Risk Informed Safety Analysis (RISA) Pathway Latest Report:
Technical and Economic Considerations for Uprate of Existing Nuclear Reactors with Cogeneration-This report delves into the potential for power uprates in the existing fleet to contribute to these decarbonization efforts, focusing on the expansion of capacity for applications such as hydrogen production and car-bon capture and sequestration. Building on previous research, the report explores re-gional market demands for hydrogen, oxygen, and carbon dioxide, financial implica-tions of oxygen and CO2 sales from high-temperature steam electrolysis systems, and the potential for direct air capture systems paired with uprated nuclear plants.
The current nuclear fleet has successfully completed a total of 172 power uprates, yielding a thermal power increase equivalent to about eight new large reactors. This report assesses the impact of these uprates and the Inflation Reduction Act of 2022 on the nuclear industry's transformation to support a decarbonized economy.