Small Modular Reactors (SMRs):Are they the wave of the future?

Alan E. Waltar* and William Stokes*** Senior Advisor, Pacific Northwest National Laboratory (Retired)

Professor and Head, Department of Nuclear Engineering, Texas A&M University (Retired)

Past President and Fellow, American Nuclear Society

** President, Columbia Basin Consulting Group

Canadian Radiation Protection Association Annual Conference

Saskatoon, Saskatchewan

June 6, 2017

Outline

I. Why SMRs?II. The ChallengesIII.The CandidatesIV. Conclusion

I) Why SMRs?1. Why Electricity?2. Brief history of commercial

reactors3. Long dry spell within the

industry4. Current status5. Utility perspectives

Electricity and human development

Main Global Drivers

for Nuclear Expansion

• Need for Stable, Long-Term Supplies of Electricity

• Energy security – geopolitical

• Carbon Emission Concerns

• However – Market Share Has Declined Over Last

Decade Due to Inexpensive Fossil (Gas & Coal)

Additional Roles for Nuclear

Can Nuclear Energy Become the Power Source of Choice ? - Economics

Reduce Front-End & Operational Costs & Take Advantage of Versatility

Supplemental Uses

• Desalination

• Process Heat

• Hydrogen Production

Nuclear Power:

Current status (as of July 2010)

• 437 nuclear

power plantsin 29 States

• 55 under

construction• expansion

centered inFar East andSouth Asia

Nuclear Power:

Status (as of January 2014)

• 435 nuclear

power plantsin 30 Countries

• 72 under

construction• expansion

centered inFar East andSouth Asia

Implications of the Near Halt in Construction of New Nuclear Power Plants in Last Couple Decades

• Key Professionals Retired or Lost to Industry

• Few Professionals Coming into the Industry

• Manufacturing Plants Shut Down

• Hence, New Construction Cost Much Higher in the Renaissance that began about 5 years ago

• Utilities now strapped to spend >$5B on new, large plants

Hence, the Principal Drivers for Small Modular Reactors

• Reduced capital costs per plant

• Meet electrical growth incrementally

• Diversity in Power Supply – Not Dependent on “Single-Shaft”

• Shorter construction schedules (modular construction)- Quicker Return

• Enhanced safety and security (some Fukushima influence & Gen IV SMRs)

• Improved quality (in-factory nuclear-module fabrication)

• Replace aging coal plants using in-place infrastructure

• Create good domestic jobs

• Markets w/Limited Power Infrastructure – Distributed Generation

II) The Challenges

1.Enterprise Startup Costs2.Governmental

Incentives

Economic Challenges Facing SMRs

•Significant investment needed to reach commercialization•On the order of $500 - $1,000 M + per design

•Can the plants be built cheaply enough?• Economies of replication > economies of scale?• Need a factory (production pipe-line) to make the price attractive• Need an attractive price to produce the orders to warrant

building the factory • Nuclear energy cost & schedule track record – high risk • No demonstrated history to offset nuclear energy cost record

•Can the operations and maintenance costs be kept down?Will simplified “inherently safe” designs translate into smaller

workforce & operation cost & comply with regulatory requirements?

Licensing Challenges Facing SMRs

• The Nuclear Regulatory Commission (NRC) not currently staffed with the required technical expertise

•Time and money required to develop staff•Potentially very long licensing time•NRC revising regulatory infrastructure for Gen III & Gen IV SMRs •NRC can license by “exemption” but cumbersome & uncertain

• Difficult for the NRC to allocate the resources if there is no serious utility buyer• “Chicken and the egg” syndrome• May need Congressional direction and funding

•Is the Regulatory Environment On a Faster Track in Canada?• Regulatory process better suited for innovation • Is there a market for SMR vendors who move the Enterprise to Canada?• How does a Canadian “license” translate elsewhere?

New U.S. Politics • Trump Team – actively looking to maintain nuclear

energy in U.S.

• Climate change not receptive argument

• Trump budget eliminated programs (LGP) and other support for renewables but also assisted nuclear

• Not likely to be supported by Congress

• Must make competitive economic sense

• Inexpensive gas and coal most likely competitors

DOE Managed Nuclear Energy Support Programs available to SMR Developers

• DOE Funding (Matching) Opportunity Announcements made awards to mPower (subsequently dissolved) and NuScale

• Gateway for Accelerated Innovation in Nuclear (GAIN) provides private companies access to federal resources on a co-funded cost basis – Currently in Round 2 Evaluations

• DOE Grants, the DOE is developing several co-funded grant programs, to support early NRC licensing costs and pre-application interactions and licensing subject-matter white-paper preparation.

• Loan Guarantee Program has issued a 2017 applications schedule with an available authorization of $12.6 Billion for nuclear energy, including SMRs and includes front-end engineering and licensing

Private Sector Nuclear Energy Support

• Breakthrough Energy Ventures (BEV) is coalition of international investors (Breakthrough Energy Coalition), chaired by Bill Gates

• Formed in expectation that private funds would be needed for climate responsive technology development

• Early stage Investment Partners – long term view for climate responsible technology development w/a return on the investment

• Target an investment pool of $1 Billion dollars

• Organized into five Grand Challenges with fifty-five Technical Quests

• The first Grand Challenge is electricity production, and

• The first Technical Quest is Gen IV Nuclear Fission

• BEV is still organizing and not ready to accept proposals

III. The Candidates

1. Water cooled2. Molten salt3. Gas 4. Liquid metals

INTEGRAL PRIMARY SYSTEM CONFIGURATION

XX

XX

XX

XXXX

XX

XXXX

XX

600 MWeLoop-Type PWR

25m

40m

IRIS

335 MWe

58m

Integral vessel configuration eliminates looppiping and external components, thus enabling compact containment and plant size

• Improves safety, reduces cost

Compliments: Dan Ingersoll

Passive removal of decay heat is enhanced by using smaller vessels

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/m)

Inside Diameter (m)

Total A/V

Pressure (bar)

Ref: P. Lorenzini, “NuScale Power: Capturing the ‘economy of small’,”

presentation at ICAPP-2010, San Diego, CA (June 2010).

Decay Heat Volume r3

Heat Removal Surface Area r2Heat Removal

Decay Heat 1/r}

mPower (B&W)

180 MWe

SMR (Westinghouse)225 MWe

HI-SMUR (Holtec)

160 MWe

NuScale (NuScale)

45 MWe

Light Water Cooled

Compliments of Dan Ingersoll

NuScale• Invented and Developed at Oregon State University

• Several years of development effort• Some $500 million invested to date

• Now under the ownership of Fluor

• Several sites under consideration for construction

• First SMR to get licensing docketed by the NRC

Thermal Power = 160 MWthElectrical Power = 50 MweCapacity Factor >95%Reactor Dimensions:

Height = 65 feetDiameter = 9 feet

Containment Dimensions:Height = 76 feetDiameter = 15 feet

Weight = 700 TonsTransport: Barge, Truck, RailCost: < $5100/KWFuel: Standard LWR fuel

17x17 arrayNo Pumps (convection only)Single Control Room

for up to 12 modules

NuScale

NuScale

NuScale

NuScale – Power Plant

• Multi-Module Design

• Scalable through Module Addition

• Targeted to Coal Plant Replacement Projects

NuScale in Transport

Safety Estimates for SMR – (Post Fukushima)

Probabilistic Risk Assessment (PRA) of Core Damage Frequency (CDF)

DesignSource: US Department of Energy

Molten Salt – Concepts

Three Basic Configurations or Designs

1. Hybrid – Standard Fuel & Molten Salts as Primary Coolant – USDOE Promotion

2. Thermal Spectrum – Liquid Molten Salt Fuel -Moderated for Thermal Spectrum – ORNL MRE Project

3. Fast Spectrum - Liquid Fuel in a Molten Salt solution operating in the Fast Spectrum

Terrestrial Energy (Canada) Integral Molten Salt Reactor (IMSR)

• Terrestrial Energy utilizes a true Molten Salt concept w/ Graphite Moderator

• Closely based on experience of ORNL MRE project w/ enhanced design features

• Robust and scalable design both through module addition or module power increase

• Most advanced concept of the several competitive vendors

Integral Molten Salt Reactor Concept

Moderator & Primary Fission Region

Integral Heat Exchanger & Primary Pump

Pump Motors & Containment Structure

Terrestrial Energy (Canada) Integral Molten Salt Reactor (IMSR)

Aggressive Development Schedule – On Track

MHR (General Atomics)

280 MWe

ANTARES (Areva)

275 MWe

Gas-Cooled

American Design French Design

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 steamenergetics 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 toassure safe shutdown

TRISO fuel particle

Core geometry also can provide passive safety

Annular core design of modular high-temperature

gas-cooled reactor improves conduction of decay

heat to the vessel for passive heat removal

PRISM (General Electric)

300 MWe

Liquid Metal Cooled

SVBR-100

(AKME Engineering,

Russian Federation)

4S(Toshiba, Japan)

10 MWe100 MWe

…………….Sodium-Cooled……………………………… …Lead-Bismuth Cooled…

NonProliferationPRO CON

Fast Reactors Long Life Cores Higher Pu Content

NOTE: Those Opposed to Fast Reactors Usually Cite the Plutonium “Problem” ---

Neglecting the Inherent Advantages of Long-Life Cores

39

Refrain from pure Pu stream during reprocessing

Transmutation

• Huge Public Concerns Over Long-Term Nuclear Waste

• Higher Actinides Produce Major Long-Term Heat Load

and Radiotoxicity in a Geologic Repository

• Hence, Considerable Incentive to Simplify Long-Term

Storage by Eliminating Higher Actinides

40

Higher Actinides: Fast Spectrum Eliminates Thermal Spectrum Produces

41

Source: FAST SPECTRUM REACTORS

Current Global Fast Reactor SMR Interests

Country Reactor MWth CoolantRussia MBIR 150 Sodium

SVBR 280 Lead- BismuthBREST-300 700 Lead

France ASTRID 600 SodiumBelgium MYRRHA 50-100 Lead-BismuthE.U. ALFRED 300 LeadU.S. PRISM (GE) 840 Sodium

DLFR (W) 500 Lead

Russian SVBR-100 (lead-bismuth cooled)

Overall Artist’s View of SVBK-100 Being Designed for Dimitrovgrad

SOURCE: http://www.bellona.org/articles/articles_2011/volga_smallcapacity

IAEA ReportStatus of Small and Medium Sized Reactor

DesignsSeptember 2012

• Light Water Cooled 18

• Heavy Water Cooled 3

• Gas Cooled 4

• Liquid Metal Cooled 7

TOTAL = 32

SMART

Status: Approved by the Korean Licensing Authorities Status: Detailed design; construction

starting in 2015

ACP-100

KoreaIntegral PWR100 MWe

ChinaIntegral PWR100-150 MWe

Two SMRs On Track to be Deployed

The World is Moving Ahead

Advanced Nuclear Energy DevelopmentIn 2016 Third Way reports 48 companies working advanced nuclear energy development – mostly private funds, many in SMR definition

Small Modular ReactorEnvironmental Footprint (Courtesy of Westinghouse – 225 MWe SMR)

Molten Salt Reactors

Liquid Metal Fast Reactors

High Temperature Gas Reactors

Water Cooled Reactors

Conclusions• Interest in SMRs growing rapidly throughout world

•Climate Concerned Governments •Climate Responsible Industry •Power Generators for cost control •Regional Regulators for coal plant replacement

• Interest from Global Governments seeking small scale, safe, affordable, & reliable power

Thank You!!!

Backup

Nuclear Power Plant Construction Costs in Korea

Const

ruct

ion C

ost

(C

ost

/kW

)

100 %

80

1st OPR1000(YG 3&4)

NthOPR1000(UC 5&6)

ImprovedOPR1000

(SK 1&2

1stAPR1400(SK 3&4)

Nth APR1400

8078

69

6160

40

20

0

Why?How is Korea Different?

Two Main Reasons:

• Top Federal Support for past half-century

• Stayed the Course after Chernobyl

UAE Nuclear Power contract

NPP turnkey package contract

Contract worth $ 20 billion +

Completion schedule

2017 - 2020

AFTER Fukushima…Obama administration continued to publicly

support nuclear power

President Obama at Town Hall Discussion on Energy in Fairless Hills, Pennsylvania (April 6, 2011)

“I want us to double the amount of electricity that we draw from clean sources. I want us to double it. And that means by 2035, 80 percent of our electricity will come from renewables like wind and solar, as well as efficient natural gas, clean coal, nuclear power. We can do that.”

• 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

Contemporary SMR designs also provide enhanced plant safety and robustness

Integral PWR

Compliments: Dan Ingersoll

125 MWe

mPower

45 MWe

NuScale

225 MWe

W-SMR

U.S. LWR-based SMR designs for electricity generation

1200 MWe

PWR

140 MWe

HI-SMUR

Gen II PWR W-SMR HI-SMUR mPower NuScale

Electrical Output (MW) 1200 225 140 125 45

Vessel Diameter (m) 4.6 3.7 2.7 3.6 2.7

Vessel Height (m) 13.4 24.7 40.2 22 13.7

Surface Area/Volume (1/m) 1.02 1.16 1.53 1.20 1.63

Surface Area/Power (relative to PWR)

1.00 7.25 13.31 11.39 15.00

Compliments: Dan Ingersoll

The American SceneHistory of U.S. operating plants prior to Fukushima

Current Global NuclearPower Scene

EUROPE

• Finland: Building a new plant

• Russia: Doubling planned by 2020

• France: New building plans announced

• UK: Going back to nuclear

• Sweden: Going back to nuclear

• Italy: Going back to nuclear(?)

ASIA

• China: 5-fold growth planned by 2020

• India: 100-fold growth planned by mid-century

USA

• Early Shutdown – Cheap Gas w/Increase in Carbon Emissions

• Exemplary Record in Severe Weather – Polar Vortex

• Federal Programs for Improved Safety & Small Reactor Support

• Private Sector Very Active on Advanced Technology Development

Many Developing Countries Pushing for Nuclear Energy Technology

New Trump AdministrationEnergy Secretary Rick Perry advocates for nuclear power

LOS ALAMOS, N.M. (AP) — U.S. Energy Secretary Rick Perry on Wednesday vowed to advocate for nuclear power as the nation looks for ways to fuel its economy and limit the effects of electricity generation on the environment. Perry made the comments during a visit to Los Alamos National Laboratory in northern New Mexico, where nuclear research has been among the main focuses since the lab's founding years during World War II. Los Alamos played a key role in the top-secret Manhattan Project to develop the first atomic bomb.

Office of Advanced Reactor Concepts

Small Modular Reactor Program

DOE Small Modular Reactor Program

SMR Program Elements:

--Enable the deployment of a fleet of SMRs in the United States

– SMR Program is a new start program for FY 2011

– Structured to accelerate the deployment of mature SMR designs based on

known LWR technology

– Conduct needed R&D activities to advance the understanding and

demonstration of innovative reactor technologies and concepts

– LWR SMR Licensing Technical Support ($452M/5-year program)

Public-Private Partnerships for design certification & licensing activities

– SMR Advanced Concepts R&D

• Conduct R&D on innovative technologies/systems/components and supportGeneric licensing work

• Collaborate with NRC on SMR licensing framework to support SMR

commercialization

Office of Advanced Reactor Concepts

Small Modular Reactor Program

DOE Actions to date in funding SMRs

• mPower Reactor (Babcock and Wilcox design) to be sited at Clinch River); funded for up to $500K over 5 years

• But….mPower announced the termination of its project!

• A second RFP is has been announced

CEFR, Near Beijing, China

Criticality 2010Full Power 2011MWth 65MWe 23.4Coolant NaConfiguration PoolCoolant Velocity (m/s) 4.7Inlet Core Temp.(C) 360Outlet Core Temp. (C) 516Fuel UO2Enrichment 64.4Fuel FormSmear Density (%) 77.6Core Diameter (m) 0.600Active Fuel Height (m) 0.450# Core Assemblies 81# Total Assemblies 703Pins/Assembly 61Plenum LocationPeak Flux (n/cm2 sec) 3.1Peak. Flux (n/cm2 sec) 2.1Peak Lin. Power (KW/m) 40Ave. Lin. Power (KW/m) 26.1Clad Material 06Cr16Ni15Mo2Mn2TiVBDuct Material 08Cr16Ni11Mo3Ti1Fuel Cycle (days) 73

• China’s First Fast Reactor

• Achieved Criticality About Two Years Ago

• Very Large Building-- sized for significant future efforts

• Next Steps: 1) Start Construction of Two BN-800 Reactors

2) Design and Build CDFR (2500MWe)

SVBR-100 Technical OverviewRussian Lead-Bismuth Cooled Reactor

Reactor / Plant280 MWt SMR using UO2 [16.1% U235] Fuel, with a nitride fuel optionPool Reactor design - based on Russian Submarine power plant with more than 80 reactor years of serviceWater shield “jacket” outside the primary reactor vessel that also serves as a post accident heat sink

Primary coolant is lead-bismuth eutectic (LBE)Eutectic alloy is about 45% Pb, 55% BiMelting Point = 123.5 ℃, Boiling Point = 1670 ℃Coolant Volume in Primary Circuit = 18 m3

Core Inlet temperature at Power = 320 ℃, Core ∆T = 162 ℃Coolant velocity through the core = 2 m/sec

Reactor CoreCore Volume = 1.91 m3, Active Fuel Height = 0.9 mFission Gas Plenum below the Fuel ColumnCore Volume Fractions: Fuel = 0.61 Steel = 0.11 LBE = 0.28Avg total neutron flux at power = 9 x 1014 n/cm2-secOxide Smear Density = 88.3% TD

Safety and Licensing Considerations

Inherent Safety CharacteristicsOperates at atmospheric pressure: No Pressure Vessel to FailLeak before break: No massive loss of coolant eventNegative Coolant density coefficient: Negative coolant void defectVery high coolant boiling point: Large margins to boiling in BDBAsModest Doppler Defect - 43¢: Small added reactivity in cool-down events

For a ULOF, we estimate core outlet temperatures may reach 704 ℃ resulting in the possibility of some cladding failures but no fuel melting.

Passive Safety FeaturesNatural Circulation Cooling when pumping power is lostDecay Removal Systems: Water Shield will act as emergency heat sinkFusible locks [melt at higher coolant pool temperatures] releasing 6 control rod bundles that fall into the core.

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 reduced emergency planning

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 capacitiesLess than 300 MWe

U.S. Coal PlantsDrivers for utility interest in SMRs