1. Small Modular Reactors and the Second Nuclear Era Daniel Ingersoll Oak Ridge National Laboratory ingersolldt@ornl.gov November 17, 2011 ET Section of AIChE

2. 2Managed by UT-Battelle for the U.S. Department of Energy Background

3. 3Managed by UT-Battelle for the U.S. Department of Energy The U.S. began developing small nuclear reactors for military applications USS Nautilus 1954-80 Nuclear Test Aircraft 1955-57 Camp Century 1960-62

4. 4Managed by UT-Battelle for the U.S. Department of Energy Navy’s experience spawned nuclear propulsion for merchant shipping N.S. Savannah 1961-71 N.S. Otto Hahn 1968-79

5. 5Managed by UT-Battelle for the U.S. Department of Energy The first commercial power plants were small prototypes Vallicetos (5 MWe) 1957 Dresden 1 (200 MWe) 1960 Shippingport (60 MWe) 1957

6. 6Managed by UT-Battelle for the U.S. Department of Energy Commercial nuclear power plants escalated rapidly in size during the 70s 0 200 400 600 800 1000 1200 1400 195519601965197019751980198519901995 Date of Initial Operation Electrical Output (MWe) 2000 U.S. plant construction during the first nuclear era

7. 7Managed by UT-Battelle for the U.S. Department of Energy Weinberg study* (1985) explored merits of smaller, simpler, safer reactors Main findings: –Large light-water reactors pose very low risk to the public but high risk to the investor –Large reactors are difficult to operate: complex and finicky –Small inherently safe (highly forgiving) designs are possible if they can be made economically –Two designs were especially promising: 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, 1985 Motivated by the dismal performance of the large plants (at that time)

8. 8Managed by UT-Battelle for the U.S. Department of Energy Process Inherent Ultimate Safety (PIUS)Safe Integral Reactor (SIR) Integral LWR designs evolved in the 80s to enhance plant robustness

9. 9Managed by UT-Battelle for the U.S. Department of Energy Non-LWR SMR designs also developed during the 80s Power Reactor Inherently Safe Module (PRISM) Modular High-Temperature Gas- cooled Reactor (MHTGR)

10. 10Managed by UT-Battelle for the U.S. Department of Energy Current Interests

11. 11Managed by UT-Battelle for the U.S. Department of Energy Interest in SMRs is reemerging Enabled by excellent performance of existing fleet of large nuclear plants Motivated by carbon emission goals, energy security concerns and economic challenges Key Benefits –Enhanced safety and robustness from simplified designs –Enhanced security from below-grade siting –Reduced capital cost—a major barrier for many utilities –Competitive power costs due to factory fabrication and modularization/standardization –Ability to add new electrical capacity incrementally to match power demand and growth rate –Domestic supply chain—no large forging bottlenecks –Adaptable to a broader range of energy needs –More flexible siting (access, water impacts, seismic, etc.)

12. 12Managed by UT-Battelle for the U.S. Department of Energy Interest in SMRs is reemerging Enabled by excellent performance of existing fleet of large nuclear plants Motivated by carbon emission goals, energy security concerns and economic challenges Key Benefits –Enhanced safety and robustness from simplified designs –Enhanced security from below-grade siting –Reduced capital cost—a major barrier for many utilities –Competitive power costs due to factory fabrication and modularization/standardization –Ability to add new electrical capacity incrementally to match power demand and growth rate –Domestic supply chain—no large forging bottlenecks –Adaptable to a broader range of energy needs –More flexible siting (access, water impacts, seismic, etc.)

13. 13Managed by UT-Battelle for the U.S. Department of Energy Interest in SMRs is reemerging Enabled by excellent performance of existing fleet of large nuclear plants Motivated by carbon emission goals, energy security concerns and economic challenges Key Benefits –Enhanced safety and robustness from simplified designs –Enhanced security from below-grade siting –Reduced capital cost—a major barrier for many utilities –Competitive power costs due to factory fabrication and modularization/standardization –Ability to add new electrical capacity incrementally to match power demand and growth rate –Domestic supply chain—no large forging bottlenecks –Adaptable to a broader range of energy needs –More flexible siting (access, water impacts, seismic, etc.)

14. 14Managed by UT-Battelle for the U.S. Department of Energy Utility interests in SMRs Affordability –Smaller up-front cost –Better financing options Load demand –Better match to power needs –Incremental capacity for regions with low growth rate –Allows shorter range planning Site selection –Lower land and water usage –Replacement of older coal plants –Potentially more robust designs Grid stability –Closer match to traditional power generators –Smaller fraction of total grid capacity –Potential to offset non-dispatchable renewables Plants >50 yr old have capacities Less than 300 MWe U.S. Coal Plants

15. 15Managed by UT-Battelle for the U.S. Department of Energy Government interests in SMRs Carbon Emission − Reduce U.S. greenhouse gas emissions 17% by 2020…83% by 2050 − E.O. 13514: Reduce federal GHG emissions 28% by 2020 Defense Mission Surety − Studying SMR deployment at DOD domestic facilities − Address grid vulnerabilities and fuel supply needs Energy and Economic Security − Pursue energy security through a diversified energy portfolio − Improve the economy through innovation and technology leadership 2005 U.S. CO 2 Emissions (Tg)

16. 16Managed by UT-Battelle for the U.S. Department of Energy Safety Considerations

17. 17Managed by UT-Battelle for the U.S. Department of Energy 1200 MWe PWR 125 MWe mPower iPWR SMR designs share a common set of design principles to enhance plant safety and robustness –Elimination of ex-vessel primary piping –Smaller decay heat per unit –More effective decay heat removal –Increased water inventory ratio in the primary reactor vessel –Increased pressurizer volume ratio –Vessel and component layouts that facilitate natural convection cooling of the core and vessel –Below-grade construction of the reactor vessel and spent fuel storage pool –Enhanced resistance to seismic events Design features that enhance plant safety for integral LWRs

18. 18Managed by UT-Battelle for the U.S. Department of Energy Integral Design: Simple and Robust Loop-type Primary System Core Pressurizer Control Rod Drive Steam Generator Pump Integral Primary System Core Pressurizer Pump Steam Generator Control Rod Drive

19. 19Managed by UT-Battelle for the U.S. Department of Energy Features of advanced SMRs may further enhance safety Advanced designs such as gas, metal and molten salt- cooled technologies may offer features that provide additional safety margin, including: –Low pressure coolants to reduce steam energetics during loss of forced circulation accidents –More robust fuel forms that survive extreme temperatures –Higher burnup fuels that reduce the volume of discharged fuel stored on-site –Advanced cladding and structural materials that survive extreme temperature conditions –Strong negative reactivity coefficients to assure safe shutdown TRISO fuel particle

20. 20Managed by UT-Battelle for the U.S. Department of Energy While SMRs offer the potential for enhanced safety and resilience against upset, this must be proven Fukushima experience emphasizes the need to fully understand the safety features –Common-cause upset modes in multi-module plants –Seismic response of below-grade construction –Reliability of passive safety systems –Quantification and demonstration of plant resilience Fukushima will influence SMR R&D priorities Fukushima Dai-ichi Unit 4

21. 21Managed by UT-Battelle for the U.S. Department of Energy Economic Issues

22. 22Managed by UT-Battelle for the U.S. Department of Energy SMR economics are promising but unproven Total project cost –Lower sticker price –Improved financing options and cost –Is a go/no-go decision for some customers Cost of electricity –Economy-of-scale 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 total generating capacity

23. 23Managed by UT-Battelle for the U.S. Department of Energy Simplified SMR construction should reduce cost and schedule Stick-built large reactor Factory fabricated small reactor

24. 24Managed by UT-Battelle for the U.S. Department of Energy Designs and Challenges

25. 25Managed by UT-Battelle for the U.S. Department of Energy mPower (B&W) 125 MWe NuScale (NuScale) 45 MWe SMR (Westinghouse) 225 MWe U.S. LWR-based SMR designs for electricity generation HI-SMUR (Holtec) 140 MWe

26. 26Managed by UT-Battelle for the U.S. Department of Energy Demonstrating the “M” in “SMR” is a key to economic viability 12-Module (540 MWe) NuScale Plant 4-Module (500 MWe) mPower Plant

27. 27Managed by UT-Battelle for the U.S. Department of Energy Gas-cooled reactor designs can provide high-temperature process heat MHR (General Atomics)PBMR (Westinghouse)ANTARES (Areva) 280 MWe250 MWe275 MWe

28. 28Managed by UT-Battelle for the U.S. Department of Energy Fast spectrum reactor designs can provide improved fuel cycles PRISM (General Electric)EM2 (General Atomics) 300 MWe100 MWe HPM (Hyperion) 25 MWe

29. 29Managed by UT-Battelle for the U.S. Department of Energy SMR Deployment Challenges Technical challenges: –All designs have some degree of innovation in components, systems, and engineering –Longer-term systems propose new materials and fuels –New sensors, instrumentation and controls development are critical to reducing capital and operational costs Institutional challenges: –Too many competing designs –Mindset for large, centralized plants –Traditional focus of regulator on large LWR plants –Fear of first-of-a-kind –“Slash and burn” political environment

30. 30Managed by UT-Battelle for the U.S. Department of Energy Prospects for local SMR

31. 31Managed by UT-Battelle for the U.S. Department of Energy Today: ORNL’s carbon footprint is driven by purchased electricity DOE GHG emissions, 2008: 4,600,000 metric tons ORNL GHG emissions, 2008 CO 2 equivalent (metric tons) Scope 1: Direct emissions 53,200 Scope 2: Indirect emissions from electricity production 226,000 Scope 3: Other indirect emissions 52,300 Total331,500

32. 32Managed by UT-Battelle for the U.S. Department of Energy ORNL’s mission-critical research facilities drive GHG emissions

33. 33Managed by UT-Battelle for the U.S. Department of Energy Oak Ridge SMR projects enables ORNL to meet GHG goals 2020 goal: 247,000 Scope 3 reduction Scope 1 reduction Scope 2 demand reduction SMR Even aggressive efficiency improvements and emission reductions are not sufficient

34. 34Managed by UT-Battelle for the U.S. Department of Energy DOE’s Oak Ridge Reservation is an attractive demonstration site TVA site adjacent to DOE facilities Support to both ORNL and Y-12 Wealth of technical expertise Supportive community TVA site adjacent to DOE facilities Support to both ORNL and Y-12 Wealth of technical expertise Supportive community Jo Will replace Clinch River Site

35. 35Managed by UT-Battelle for the U.S. Department of Energy TVA is pursuing the mPower SMR Generation mPower –125-150 MWe integral PWR –Utilizes standard UO 2 LWR fuel –4-5 year refueling interval –Reactor vessel: 3.6 m diameter and 22 m tall –TVA signed Letter of Intent on June 16, 2011 to build up to 6 mPower modules at the Clinch River Site in Oak Ridge, TN –TVA expects to submit Construction Permit application in 2012 –B&W will follow with a Design Certification application in 2013 Pressurizer Steam Generator Reactor Coolant Pumps Control Rod Drive Mechanisms Core

36. 36Managed by UT-Battelle for the U.S. Department of Energy Notional implementation schedule Prepare Design Certification Application Clinch River Project – 10CFR50 Process PSAR and Complete DCA Submit CPA NRC CPA Review CP FSER CP Issuance PSAR ER Prepare Operating License Application Submit OL Application NRC Review Operating License Applic. FSER Issued Pre-Op Testing OL Issuance Fuel Load Start-up Testing Submit DCA NRC DCA Review DCA Scope Freeze DC Rule COL Issuance 10CFR52 COLA PreparationNRC COLA Review Final DC Rulemaking Construction/ITAAC ASER Issued COLA Submittal LWA 1 st Unit Prepare CPA mPower DCD and COLA – 10CFR52 Process

37. 37Managed by UT-Battelle for the U.S. Department of Energy Bottom Line SMRs can extend clean and abundant nuclear power to a wider range of energy demands Several technical and institutional challenges must be solved and demonstrated Oak Ridge may again be a pioneer in nuclear energy “If commercially successful, SMRs would significantly expand the options for nuclear power and its applications.” - Steven Chu, Wall Street Journal, 3/23/10