Overview of Small Modular Reactor Research at ORNL

Transcription

1 Overview of Small Modular Reactor Research at ORNL INMM Central Region Chapter Fall Training Event Gary Mays, Group Leader Advanced Reactor Systems & Safety Reactor and Nuclear Systems Division Oak Ridge National Laboratory Oak Ridge, Tennessee September 24, 2013

2 ORNL has become DOE s largest science and energy laboratory $1.6B budget 4,400 employees Most powerful open scientific computing facility 3,000 research guests annually World s most intense neutron source $500M modernization investment World-class research reactor Nation s largest materials research portfolio Nation s most diverse energy portfolio Managing billion-dollar U.S. ITER project 2 Managed by UT-Battelle 2 for the U.S. Department of Energy

3 Weinberg Study* (1985) Introduced the Notion of Smaller, Simpler, Safer Reactors Foreshadowing of SMRs Motivated by lessons learned from the first nuclear era Main findings: Incrementally-improved, post-tmi LWRs pose very low risks to the public but investor risks and high, uncertain capital cost may limit market viability Large LWRs are too complex and sensitive to transients Inherently safe concepts are possible and should be pursued, such as: The Process Inherent Ultimately Safe (PIUS) reactor The Modular High-Temperature Gas-Cooled Reactor (MHTGR) *A. M. Weinberg, et al, The Second Nuclear Era, Praeger Publishers,

4 Understanding DOE s SMR Programs First To Provide Context for ORNL Roles DOE SMR Program Mission: Expansion of nuclear power to a broad range of customers and energy applications by demonstrating the affordability, flexibility, and economic competitiveness of new simplified SMR designs DOE SMR Program divided into two principal elements: SMR Licensing Technical Support (LTS) ($452 over 5 years) Objective: Promote accelerated deployment by supporting design certification and licensing requirements via cooperative agreements with industry partners and support resolution of SMR generic issues. Advanced SMR R&D Program Initiated FY12 Objective: Conduct R&D on capabilities and technologies to support development of advanced SMR concepts for deployment in mid- to longterm future => innovative concepts using non-lwr coolants such as liquid metal, helium, or liquid salt. 4

5 DOE LTS Program Has Reached One Agreement with Second One TBA Shortly on Facilitating Deployment of SMRs m-power America Partnership first awardee B&W / TVA / Bechtel LTS target commercial 2022 FY12: $67 M; FY13: $65 M Second award to be announced soon Focus on innovative technologies LTS target commercial 2025 ORNL support for LTS Programmatic planning Addressing generic issues Cutaway View of m-power 2-Unit SMR 5

6 DOE Advanced SMR Program Has Distinctly Longer-term Focus Program Objectives: Conduct evaluations of advanced SMR designs Support improvements in the safety, performance, and economics of SMR designs Conduct R&D to support licensing and deployment of advanced SMR designs Advanced SMR Program Structure: Develop assessment methods for evaluating AdvSMR technologies Develop/testing of materials, fuels, and fab methods Resolve key regulatory issues Develop advanced I&C and human-machine interfaces 6

7 Intrinsic Design Features of ipwrs Offer Safety and Economic Incentives Integral design features * Enhances safety and smaller footprint * Increased reactor coolant inventory in vessel * Increased pressurizer volume * Smaller radionuclide inventory * Increased height-to-diameter aspect ratio facilitates natural convection cooling of core and vessel * Underground siting enhances resistance to seismic and security issues 7

8 ORNL Leads AdvSMR Instrumentation, Controls, and Human-Machine Interface (ICHMI) Research Pathway Coordinating Work w/doe Labs ICHMI research is needed to meet unique challenges and opportunities of Advanced SMRs Unique Operational and Process Characteristics Unconventional dynamic behavior and distinctive architectures Extended operation and longer fuel cycles Different coolants and more extreme environments Assured Affordability Lower capital costs Reduced plant operations and maintenance costs Enhanced Functionality Multi-unit plant management Multiple product streams Flexible operability ORNL Lead: Richard T. Wood 8

9 AdvSMR ICHMI Pathway Consists of 9 Research Projects Johnson Noise Thermometry for Drift-Free Temperature Measurements In-vessel Optical Measurements for Advanced SMRs Concepts of Operation for Multi-Modular SMR Plants Framework for Human-Automation Collaboration Supervisory Control of Multi-Modular SMR Plants Impact of Active Control on Passive Safety Characteristics of Advanced SMRs Prototypic Prognostic Technique Demonstration for SMR Passive Components Enhanced Risk Monitors with Integrated Equipment Condition Assessment Modeling Tools for Dynamic Behavior Simulations of SMRs ORNL Projects 9

10 Measurement and Control Projects Conducted for AdvSMRs at ORNL Johnson Noise Thermometry Develop and demonstrate a drift free Johnson noise-based thermometer suitable for deployment near core in advanced SMR plants Supervisory Control for Multi-Modular SMRs Develop and demonstrate functional architectures to enable integration of control, diagnostics, and decision for highly automated multi-unit plant operation Project activities are to demonstrate: Auto-calibrating temperature measurement capability Implementation of dual-mode resistance and Johnson noise thermometer in a rugged, integrated prototype form Project activities enable: Definition of supervisory control requirement Establishment of a functional architecture Generation of baseline supervisory control functional elements Demonstration of supervisory control capabilities for a simulated representative multi-unit SMR plant 10

11 ORNL Leads AdvSMR Materials Research Pathway Focus of Materials Pathway is to conduct: Basic R&D on new materials to enable new innovative SMR designs Applied R&D to fully develop, qualify, and demonstrate current materials in SMR designs Objectives are to: Address long-term design needs for advanced materials Reduce unnecessary conservatism in design methodology Gain understanding of long-term degradation mechanism Support code qualification activities of candidate materials 11

12 Current AdvSMR Materials Projects Fall Into Four Primary Areas R&D to support Alloy 617 code case activities High temperature design methodology IHX for HTGR at 900 C Low temperature aging evaluations at 650 C (creep / fatigue) Advanced ferritic/martensitic steels Improve creep-fatigue design methodology Material evaluation on aging effects to 60 years Thermal aging effects on fracture toughness Creep fracture of structural alloys Design code development for composite core components for high temperature reactors (SiC-SiC) Develop & maintain Gen IV Materials Handbook as repository of U.S. and international VHTR structural materials ORNL Projects 12

13 Two-Bar Thermal Ratcheting Test Setup for Alloy 617 Two-bar thermal ratcheting test enables development and verification of material models for inelastic analysis; and verification of E-PP strain limits code case Bar 1 Temp. 1 Constant Load Rigid Rigid P Bar 2 Temp. 2 P1, u1 Bar 1 Temp. 1 u1 = u2 P1+P2 = P P2, u2 Bar 2 Temp. 2 Two servo-hydraulic test machines are coupled electronically to allow for: - Equal amounts of elongations at all times - Sum of loads equal to preselected total load at all times 13

14 ORNL is Engaged in AdvSMR Safety and Licensing Support Pathway Focus of Pathway is to conduct: Resolve key regulatory issues as identified by NRC and industry Development of analytical tools and assessment methods to model SMR that reflect design differences Key research areas: Severe accident heat removal testing Advanced reactor framework development Probabilistic risk assessment AdvSMR site screening Safeguards and Security ORNL Projects 14

15 Need for a Licensing Framework for Advanced Reactors Identified During 2012 DOE instituted an Advanced Reactor Concepts Technical Review Panel (TRP) process to evaluate viable reactor concepts from industry and to identify R&D needs. TRP members and reactor designers noted the need for a regulatory framework for non-light water advanced reactors. Also in 2012, in response to Congressional direction, the NRC provided a report to Congress on advanced reactors. The NRC noted the need for regulatory guidance for non-light water reactor designs. 15

16 Purpose of Licensing Framework Initiative is to Reduce Licensing Uncertainty 10 CFR 50 requires the establishment of principal design criteria derived from the General Design Criteria of Appendix A. Since GDCs in Appendix A are specific to light-water reactors (LWRs), this requirement is especially challenging for potential future licensing applicants pursuing advanced (non-lwr) technologies and designs. DOE-NE and NRC agree that consideration should be given to pursuing the following objective: Develop generic GDCs (derived from Appendix A of 10 CFR 50) and develop technology-specific GDCs for at least one reactor type (TBD) to supplement the generic GDCs for compliance with ,52.47 and Webinar to be held tomorrow (Sep 25) to Describe the initiative Explain how industry can provide input and participate Collaborative effort among DOE labs: INL, ORNL, and ANL 16

17 ORNL PRA-Related Support Focusing on Developing Licensing Basis for AdvSMRs Development of Surrogates for Core Damage Frequency and Large Early Release Frequency for AdvSMRs Evaluation based on accepted Defense-in-Depth Approach For LWRs and most advanced reactors Physical barriers Fuel/fuel cladding Primary system boundary Containment Operational barriers Emergency response Generate preliminary list of initiating events for HTGRs and SFRs that challenge plant control and safety systems 17

18 OR-SAGE Site Screening Tool Applied for Evaluating Potential Sites for SMRs Oak Ridge Siting Analysis for power Generation Expansion (OR-SAGE) Applies Geographical Info System Tools & Models Adapted using EPRI 2002 Siting Guide Uses 28 GIS datasets to scan 1.8 B acres Grid structure each cell is 100 x 100 m (2.5acres) => 27% of U.S. candidate area for SMRs for a 50 acre footprint 18

19 Examples Show Wide Range of Analysis Capability SMR Hypothetical Plant Placement Using ORNL Siting Algorithm Adding Layers for Electrical Transmission Transportation Systems is Straightforward Composite Map Shows Degree of Potential Siting Challenges Identifying Suitable SMR Areas Versus Projected Increases In Population Yellow => SMR-only base map Green => Base map for all reactor types Red => Area of population growth Blue => Area of population decline Based on select input values 19

20 Characterization of CRBR Site for SMR Using OR-SAGE CRBR Aerial View Screening Criteria Applied 20

21 ORNL Leading Analyses to Evaluate Reality of Anticipated SMR Economic Benefits Scope Define and model the economic characteristics of potential small reactor deployment compared to gigawatt-class reactor deployment Based on ipwrs to generate baseline for future advanced reactor systems Evaluate effects of Standardized factory fabrication and modular construction Economies of volume (build more) versus economies of scale (build bigger) Principal Elements: Develop economics model framework for SMR effects such as Serial construction of multiple units Time-dependent capacity factor to reflect generation of operational experience Collect input from industry (utilities, fuel cycle facilities, construction firms) to inform the model parameters Important for multiple unit construction Perform economics analysis on SMR deployment scenarios 21

22 Quantifying Factors Offsetting the Economy of Scale Penalty (Source: C. Mycoff, WEC) Economy of Scale: Assumes SMR is scaled version of large plant Relative SMR Overnight Cost Multiple Units Learning Build Schedule & Unit Timing Plant Design Multiple Units: Cost savings for multiple units at same site Economy of Scale Learning: Cost savings for additional units built in series Build Schedule: Reduced interest during shorter construction time Unit Timing: Cost savings from better fit of new capacity to demand growth Plant Design: Cost savings from design simplifications x 335 Plant Capacity (MWe)

23 SmAHTR Design Shows Promise for High-Temperature Heat Production Small, modular Advanced High Temperature reactor (SmAHTR) has been designed for modular, factory fabrication, and truck transport 125 MW th Plate assembly fuel Cartridge core Integral primary heat exchangers Technology development requirements for small and large FHRs is virtually identical 9 m 3.6 m 23

24 ORNL s SMR Concept SmAHTR - is A Cartridge Core, Integral-Primary-System Fluoride High- Temperature Salt-Cooled Reactors (FHR) Overall System Parameters Parameter Value Power (MWt) 125 Primary Coolant 2 7 LiF-BeF 2 Primary Pressure (atm) ~1 Core Inlet Temperature (ºC) 650 Core Outlet Temperature (ºC) 700 Core coolant flow rate (kg/s) 1020 Operational Heat Removal Passive Decay Heat Removal Reactor Vessel Penetrations 3 50% loops % loops None ORNL is lead on R&D program for developing large 3400 MWt central station AHTR (TRISO fuel salt cooled) 24

25 DOE s Oak Ridge Reservation is an Attractive Demonstration Site Clinch River Site Jo Will replace Support ORNL in helping DOE reduce GHG goals Dedicated secure source - power island for grid security Meet increasing power demands 25

26 Staff supported NRC in developing new risk-informed approach for licensing Small Modular Reactors Approved unanimously by NRC Commissioners Represents a significant change for NRC in licensing future reactors Provides a framework for a graded approach to review systems, structures, and components (SSCs) Safety-related Nonsafety-related ORNL contribution Led intra-doe lab team in evaluating the two leading ipwr SMR designs to categorize SSCs Successfully applied new approach for selected SSCs 26

27 27 Backup Slides

28 Summary Design Info 1 Shows Commonalities in ipwr SMR Concepts Design Parameter/ SMR m-power NuScale West. Holtec NGNP Alliance Reactor Power, MWt Electrical Output, MWe Outlet Temperature 609 F 575 F 566 C Coolant Light Water Light Water Light Water Light Water Helium Fuel Design Std PWR 2 Std PWR 2 Std PWR 2 Std PWR 2 TriSO particle Refueling, years full power days Licensing Plan Design Certification Design Certification Design Certification Construction Permit Construction Permit 1 Source: Briefing by Mike Mayfield, NRC-NRO to DOE SEAB on SMRs, May 30, Nominal half height 17x17 bundles 28

29 Interest in Smaller Sized Reactor Designs Based on Positive Value Proposition and Multiple Potential Markets Benefits Reduce capital outlay Improved fabrication (quality) and construction logistics due to modular designs Enhanced safety (robustness) and security Operational flexibilities (broader applications) Can meet increased electricity demands incrementally Applications Smaller utilities Replacing/repowering older coal plants Countries with financing or infrastructure constraints Distributed power needs (e.g. military base islanding) Non-electrical (process heat) customers 29

30 ORNL Is Indirectly Involved With Potentially First SMR to Be Deployed by TVA Source: John Kelly, DOE-NE 30

31 Staggered Build of SMRs Reduces Maximum Cash Outlay (Source: B. Petrovic, GaTech) Revenue (US$ million) Comparison of 1 x 1340 MWe Plant Versus 4 x 335 MWe Plant SMR1 SMR Construction SMR2 SMR3 SMR4 Based on simplified model Max Cash Outlay = $1.4B LR Construction Max Cash Outlay = $2.7B Years From Start of Construction 31

32 Size Specific Issues Suggest Re-examining Regulatory Approach Simplifies design by eliminating loop piping & external components Enhances safety eliminates major classes of accidents No large pipes in primary circuit means no large break LOCAs Increased water inventory means slower response to transients Internal CRDMs means no rod-ejection accidents Reduced source term Improved decay heat removal Compact containment enhances siting and security 32

33 Policy Issues* That NRC Staff Have Reviewed to Provide Info to NRC Commissioners NRC SECY Document SMR Policy or Technical Issues Security Regulatory Framework for Certifying, Approving, and Licensing SMRs Decommissioning Funding Assurance for SMRs Insurance and Liability Regulatory Requirements for SMRs Feasibility of Including Risk Information in Categorizing Structures, Systems, and Components as Safety-Related and Non Safety-Related Development of an Emergency Planning and Preparedness Framework for SMRs Staff Assessment of Selected SMR Issues Identified In SECY Operator Staffing for Small or Multi-Module Nuclear Power Plant Facilities License Structure for Multi-Module Facilities Related to SMRs Use of Risk Insights to Enhance the Safety Focus of SMRs Potential Policy, Licensing, and Key Technical Issues for SMR Designs * Source: 33

34 Deployment of SMRs With Multiple Modules Presents Unique Issues to be Evaluated Multiple deployment options for modules Identification of shared systems How to employ PRA Implementation of control system architectures Reactor operator requirements Control room design/layout Licensing of construction and operation of subsequent modules with operating modules ITAAC Define Design Basis Threat with several small reactors operating at one site 34

35 Economic Benefits for SMRs Focus on Affordability Total project cost Smaller plants should be cheaper Improves financing options and lowers financing cost May be the driving consideration in some circumstances Cost of electricity Economy-of-scale (EOS) works against smaller plants but can be mitigated by other economic factors Accelerated learning, shared infrastructure, design simplification, factory replication Investment risk Maximum cash outlay is lower and more predictable Maximum cash outlay can be lower even for the same generating capacity 35

36 FHRs Are Important to the Nation as a Potential Future Primary Electricity and Gasoline Energy Source Large FHRs have transformational potential to provide lower cost, high efficiency, large scale electrical power May be cheaper than LWRs due to higher thermal efficiency, low-pressure, and passive safety Small, modular FHRs can be cost effective, local process heat sources High temperature, liquid cooling enables efficient hydrogen production Domestic oil shale based gasoline production requires large-scale, distributed process heat FHRs have a high degree of inherent passive safety No requirement for offsite power or cooling water Low-pressure primary and intermediate loops Plant concept and technologies must be matured significantly before the potential for FHRs can be realized Lithium enrichment must be reindustrialized Tritium extraction technology must be developed and demonstrated Structural ceramics must become safety grade engineering material Safety and licensing approach must be developed and demonstrated April 2012 CAS Visit 36 36