Small Modular Reactors and Very High Temperature Reactors

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Small Modular Reactors and VHTR

Small Modular Reactors and Very

High Temperature Reactors

Phillip Finck

Chief Nuclear Research Officer

December 5, 2011


Part 1: Small Modular Reactors

2


Some Basic Terminology

• IAEA definition of “SMR” (small and medium reactor):

Small:

Medium:

Large:

< 300 MWe

300-700 MWe

> 700 MWe

}

Small and Medium

Reactors

• DOE definition “SMR” (small

modular reactor):

– Less than 300 MWe output

– Factory fabrication and

rail/road transportable to site

– Operated as multi-module

plant

Ft. Belvoir

3


The First Commercial Plants Were Small Prototypes

Vallecitos

5 MWe

1957

Dresden 1

200 MWe

1960

Shippingport

60 MWe

1957

4


Electrical Output (MWe)

Commercial Power Plant Size Increased Rapidly

During the 1970s

1400

1200

1000

800

600

U.S. plant construction

during the first nuclear era

400

200

0

1955 1960 1965 1970 1975 1980 1985 1990 1995

Date of Initial Operation

2000

5


Weinberg Study* (1985) Explored Merits of

Smaller, Simpler, Safer Reactors

• Motivated by the dismal performance of

the large plants (at that time)

• 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

6


Interest in SMRs is Reemerging

• Enabled by excellent performance of existing fleet of

large nuclear plants

• Motivated by carbon emission and energy security

concerns

• 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.)

7


Small Reactor Designs Share a Common Safety

Philosophy

• Eliminate potential accident initiators if

possible

EXAMPLE: Integral system to eliminate large pipe

loss-of-coolant accident

• Reduce probability of an accident

occurring

EXAMPLE: Lower radiation exposure of reactor vessel

reduces likelihood of pressurized thermal shock

accident

• Mitigate consequences of potential

accidents

EXAMPLE: Increased volume of primary coolant slows

down heat-up transient

8


Fukushima Will Influence SMR R&D Priorities

• While SMRs offer the potential for enhanced safety

and resilience against upset, performance must be

proven

• Fukushima experience emphasizes the need to fully

understand 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 Dai-ichi Unit 4

9


Fabrication and Construction Benefits

• Eliminate large forgings from foreign suppliers

• Substantial in-factory fabrication; less site-assembly

– Reduces schedule uncertainty

– Improves safety/quality

– Reduces cost

• Reduced size and weight for

easier transport to site

– Access to a greater number

of sites

– Allows parallel construction of nuclear plant and balance of plant

10


Operational flexibilities

• Site selection

U.S. Coal Plants

– Simplified emergency

99% of plants > 50 years old have

planning zone

less than 300 MWe capacity

– Broader seismic conditions

– Lower land and water usage

• Load demand

– Better match to power needs

– Repowering of coal plants

• Demand growth

– Add (and pay for) smaller

increments of new capacity

• Grid stability

– Closer match to traditional power generators

Smaller fraction of total grid capacity

11


Economic benefits

• Total project cost

Smaller plants should be cheaper

– Improved financing options and reduced financing cost

– May be the driving consideration 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 generating

capacity

12


U.S. LWR Based SMR Designs for Electricity

Generation

Pressurizer

Pressurizer

Containment

Vessel

Steam Generator

Steam Generator

Reactor

Vessel

Reactor Coolant

Pumps

Control Rod Drive

Mechanisms

Reactor Coolant

Pumps

Steam

Generator

Core

Control Rod

Drive Mechanisms

Core

Core

Westinghouse SMR

mPower (Babcock & Wilcox)

NuScale (NuScale)

200 MWe class 125 MWe 45 MWe

13


Gas-Cooled Reactor Designs Can Provide High

Temperature Process Heat

MHR (General Atomics) PBMR (Westinghouse) ANTARES (Areva)

280 MWe 250 MWe 275 MWe 14


Fast Spectrum Designs Can Provide Improved

Fuel Cycles

PRISM (General Electric)

HPM (Hyperion)

EM2 (General Atomics)

311 MWe 25 MWe 100 MWe

15


SMR Challenges – Technical

• All designs have some degree of innovation in components,

systems, and engineering, e.g.

– Integral primary system configuration

– Internal control rod drive mechanisms and pumps

– Multiplexed control systems/interface

• Longer-term systems strive for increased utility/security

– Long-lived fuels and materials for extended operation

– Advanced designs for load-following and co-generation

• Sensors, instrumentation and controls development are likely

needed for all designs

– Power and flow monitoring in integral systems

– Advance prognostics and diagnostics for remote operations

– Control systems for co-generation plants

16


SMR Challenges – Institutional

• Too many competing designs

• Mindset for large, centralized plants

– Fixation on economy-of-scale

– Economy-of-hassle drivers

– Perceived risk factors for nuclear plants

• Traditional focus of regulators on large, LWR plants

– Standard 10-mile radius EPZ (in the U.S.)

– Staffing and security force size

– Plant vs module licensing

• Fear of first-of-a-kind

– New business model as well as new design must be compelling

17


Part 2: Very High Temperature

Reactors

18


HTGR Technology Well Established

PROTOTYPE PLANTS

DRAGON – 20 MWt

(U.K.)

1964 1975

AVR – 46 MWt

(FRG)

1967 1988

PEACH BOTTOM 1 – 115 MWt

(U.S.A.)

1967 1974

HTTR – 30 MWt

(JAPAN)

1999 - present

HTR-10 – 10 MWt

(CHINA)

2000 - present

DEMONSTRATION PLANTS

FORT ST. VRAIN – 842 MWt

(U.S.A.)

1976 1989

THTR – 750 MWt

(FRG)

1986 1989

Photos courtesy of GA

19


Two versions of HTGRs: Prismatic and Pebble

Bed Designs Dependent On Fuel Form

Prismatic

(Dragon, Peach Bottom, FSV, etc.)

Pebble-bed

(AVR, THTR, SA PBMR, China, etc.)

Photos and figures courtesy of GA and PBMR-Pty 20


HTGRs Offer Economic Advantages

High thermal efficiency

• Reduced emergency

planning costs

• Simplified safety systems

• Lower component

contamination levels

Increased public acceptance

Figure courtesy of GA

21


HTGRs Feature Passive Safety

Figure courtesy of GA

• Inert single-phase helium

coolant

• Massive graphite core

moderator

High temperature

– Large heat capacity

– Low power density

• slow heatup

• Coated particle fuel

High temperature

– Fission particle retention

• Large negative temperature

coefficient

Courtesy Global Virtual LLC 22


Advantages of VHTRs: Safety Advantages

Courtesy Global Virtual LLC

23


Possible Residual Heat Removal Paths

when Normal Forced Cooling System Is Unavailable

Air Blast

Heat Exchanger

Natural Draft,

Air Cooled

Passive System

Shutdown

Cooling System

Heat Exchanger

and Circulator

Reactor

Cavity

Cooling

System

Panels

A) Active Shutdown

Cooling System

B) Passive Reactor Cavity

Cooling System

Defense-in-Depth Buttressed by Inherent

Characteristics

C) Passive radiation

and conduction of

residual heat to

reactor building

(Beyond Design

Basis Event)

24


TRISO-Coated Particle Fuel is at the Heart of the

High Temperature Gas Reactor Concept

(provides technical basis for co-location)

Key aspects of TRISO Fuel:

• German industrial

experience demonstrated

that TRISO -coated particle

fuel can be fabricated to

achieve high quality levels

with very low defects

• This fuel is very robust with

no failures anticipated

during irradiation and under

accident conditions

• Fuel form retains fission

products resulting in a high

degree of safety

25


Advantages of HTGRs: Robust High

Performance Fuel

High burnup fuel

– Less waste

– More energy produced per unit mass

of uranium

– Better fuel utilization

• Robust

– Ultra high quality, very low fabrication

defects

– Large margins to fuel failure

High fission product retentiveness

• Flexible fuel cycle

– U, Th, or Pu

26


Control Rods Shut Reactor Down by Gravity –

Also Can Shut Down by Negative Temperature Coefficient

CONTROL ROD DRIVE

SUPPORT SURFACE

GAMMA SHIELDING

PELLETS SIZED TO

PRECLUDE BRIDGING

HOPPER

CONTROL ROD DRIVE

MECHANISM

CONTROL ROD GUIDE

TUBE

RESERVE SHUTDOWN

STORAGE HOPPER

INSULATION

FLOATING SEAL RING

GATE (CLOSED)

RESERVE SHUT

DOWN TUBE

Safety Feature:

Automatic Scram on

loss of power

REACTOR VESSEL

INNER NEUTRON

CONTROL ASSEMBLY

(6)

OUTER NEUTRON

CONTROL ASSEMBLY

(12)

31' 9"

NEUTRON SHIELDING

RESERVE SHUTDOWN

STORAGE HOPPER

CONTROL ROD GUIDE

TUBES

RESERVE SHUTDOWN

CONTROL EQUIPMENT

NEUTRON

SHIELDING

GATE (OPEN)

• Drives located in Reactor

Vessel Head

• Neutron shielding protects

drive

• Control rods suspended by

cables

• Guide tubes connect rod to

top- of-core

• Reserve shutdown pellets

in hoppers

• Dropped into core when

needed

27


Several Factors Motivate Recent U.S. HTGR

Interest

High temperature applications

– Process heat

– Hydrogen production (as a chemical feedstock)

• Inherent safety

– Simplified licensing and emergency planning requirements

– Reduced safety requirements

– More flexible siting requirements

• Political

– Reduce greenhouse gas emissions

– Energy Policy Act of 2005 (EPAct)

– Energy independence

– Grow US nuclear infrastructure

– Increased public acceptance

28


$ / MMBTU

Thousands of Barrels per Day

Addressing the Energy Challenge…

• Volatile prices for oil and natural

gas

• Dependence on foreign sources

• Increased risk of climate change

with burning of fossil fuels

NYMEX Natural Gas Futures Close

(Front Month)

3/08 l l l l l 9/08 l l l l l 3/09

Close

Net Oil Imports and

Price of Oil

60% of oil and 16% of

natural gas used in U.S.

is imported

29


Energy Production and Consumption in U.S. –

the Potential Market

U.S. Primary Energy Flow by Source and Sector, 2009

(Quad -- Quadrillion (1×10 ) Btu)

15

U.S. Greenhouse Gas Emissions

by Sector

(million metric ton equivalent)

(AEO 2010, May 2010)

Transportation

1845 Mt

Residential

1194 Mt

Industrial

1434 Mt

Commercial

1034 Mt

5,507 Mt Total

U.S. Industry is responsible for 26% of U.S. carbon footprint

30


Beyond Electricity – Applications of HTGRs

High Temperature Reactors can provide energy

production that supports the spectrum of industrial applications,

including the petrochemical and petroleum industries

31


Industrial Applications – the Principal Market

The Opportunity — Providing High Temperature Process Heat

and Electricity Without Burning Hydrocarbon Fuels

Petrochemical

(170 plants in U.S.

– 6.7 quads*)

Petroleum Refining

(137 plant in U.S.

– 3.7 quads)


Fertilizers/Ammonia

(23 plants in U.S. – 0.3 quads

NH3 production)

Coal-to-Liquids

(24 – 100,000 bpd new plants)

Project 250 GW HTGR application

Hydrogen Production

(60 – 600 MWt HTGR Modules)

Oil Sands/Shale

(43 – 600 MWt HTGR Modules)

*Quad = 1×10 15 Btu (293 MM MWth) annual energy consumption

32


Impact of HTGRs

on End User

CO 2 Emission

CO 2

Emissions

(Mt/day)

Technology

Today

Limited

HTGR

supply of

energy only

A B C

5868

1534

1283

(1983)

117

(1953)

235

(1646)

11

(742)

Natural Gas

600K lb/hr stream

3 HTGRs

(600MWt ea)

Natural Gas

70 million

SCF/day

1 HTGR

(600MWt)

Feedstock

Hot Gas

330 MWe

Feedstock,

Power

92% of coal goes

to product

Thermal Cracking

614 TPD CO 2

117 TPD

CO 2

2,940 TPD

Urea

92% of coal goes to product

3,780 TPD Ammonium Nitrate

Steam

11 TPD

CO 2

Ethylene

A. Petrochemical Plant Co-generation

B. Ammonia and Derivatives Production

HTGR

supply of

steam,

electricity

and hot gas

614 28 11

(sequestered values)

>95% of

carbon goes

to product

4,891 TPD

Coal

8 HTGRs

(600MWt ea)

Heat + power

Feedstock

O 2

H 2

Syngas

Hydrogen and

oxygen production,

co-electrolysis, coal

drying, tail gas

steam reformer,

product upgrading,

power generation

+

8,950 BPD

Naphtha

C. Coal to Diesel and Naphtha

19,129 BPD

Diesel

33


Multiple Configurations Developed by HTGR Suppliers

Electricity Only

(Brayton Cycle)

Steam Cycle

Electricity and Hot

Gas Cycle

Steam and Hot

Gas Cycle

Steam and Hot

Gas Cycle

Nuclear

Heat

Supply

System(s)

Primary

Helium

Primary

Circulator

Steam

Generator

Intermediate

Heat

Exchanger

Return Feed

Steam to

Steam Turbine

Generator and

industrial

processes

Steam

Return

High

Temperature

Fluid to

Industrial

Processes

High Temperature

Fluid to Industrial

Processes

Gas Return

Secondary

Circulator

Gas Supply

Intermediate

Heat

Exchanger

Primary

Circulator

Primary

Helium

Nuclear Heat

Supply

System(s)

Primary

Circulator

Primary

Helium

Steam

Generator

Return Feed

Steam to Steam

Turbine

Generator and

industrial

processes

Supply

Steam

Process Heat Options 34


Electricity Production Price, $/MWhe

Price of Steam, $/1000lbs

Electricity and Steam Production

Electricity Production Price Versus

Price of Natural Gas, $/Mwhe, and Carbon Credits, $/metric ton CO 2eq

Comparison of Production Pricing for HTGR and CCGT Plants

35

Comparing Price of Steam Generated by an HTGR and a CCGT versus

Price of Natural Gas and Cost of GHG Emissions

160

140

CCGT

$50/MT CO 2 Cost

30

CCGT, $50/MT

CO 2 Emissions Cost

25

120

100

80

60

~$4/MMBtu

CCGT

No CO 2 Cost

~$8.5/MMBtu

HTGR

20

15

10

5

~$4/MMBtu

CCGT, No CO 2

Emissions Cost

~$7/MMBtu

HTGR

40

0 2 4 6 8 10 12 14 16 18

0

0 2 4 6 8 10 12 14 16

Natural Gas Price, $/MMBtu

Price of Natural Gas, $/MMBtu

Economic Factors

HTGR Plant Capital Cost $1,700/KWt

CCGT Capital Cost $625/KWt

Debt 80%

Internal Rate of Return 15%

Financing Interest 8%

Financing Term 20 years

Tax Rate 38.9%

35


HTGR Technology Development and Qualification

Needs

High Temperature Materials

Characterization, Testing and

Codification

Graphite Characterization,

Irradiation Testing,

Modeling and Codification

Fuel Fabrication,

Irradiation, and Safety

Testing

Design and Safety Methods

Development and

Validation

36


Overall thermal to hydrogen efficiency (%) l

kg of H2 per barrel

High Temperature

Steam Electrolysis

Efficient production of H 2 or syngas

(2H 2 +CO) using nuclear heat and electricity

60

50

40

30

20

10

0

65% of max possible

INL, HTE / He Recup Brayton

INL, LTE / He Recup Brayton

INL, HTE / Na-cooled Rankine

INL, LTE / Na-cooled Rankine

INL, HTE / Sprcrt CO2

INL, LTE / Sprcrt CO2

SI Process (GA)

MIT - GT-MHR/HTE

MIT AGR -SCO2/HTE

300 400 500 600 700 800 900 1000

T (°C)

HTSE stacks are

compact and

simple, using SOFC

technology

H 2 is needed to upgrade carbon

sources to gasoline, diesel or jet fuel

45

40

35

30

25

20

Co-electrolysis of

H 2 O and CO 2

produces syngas,

which can be

catalytically

combined to form

lubricants, motor

fuels and a wide

variety of

hydrocarbons.

15

10

5

0

light

sweet

crude

heavy oil

or

bitumen

oil shale

Biomass

(woody)

Carbon Feedstock

coal

Fisher-

Tropsch

H2

HTSE was selected

as the most

promising way to

produce H 2 using

nuclear energy.

July 2009

INL has established itself as the world

leader in developing and demonstrating

HTSE and co-electrolysis technologies


Summary

• SMR

– SMRs can extend clean and abundant nuclear power to a wider

range of energy demands

– Emerging SMR designs are based on decades of experience

– Several technical and institutional challenges must be

addressed and demonstrated

• VHTR

High temperature gas-cooled reactors can enable nuclear

energy to enter the non-electrical applications market helping to

reduce the large carbon footprint in that sector

– Passive safety characteristics of the technology make it an ideal

reactor to co-locate with industrial installations

– Technology development is underway and is demonstrating the

outstanding attributes of VHTRs

38


China and U.S. share similar patterns of demand,

supply growth, and sustainability

• Rapid growth, reliance on coal for

electricity and heat, need and

pursuing everything

• Both countries heavily reliant on oil,

and this will not change; both seek

to green coal

• China slow to start its civil nuclear

program but with ambitious plans —

70 GWe operating by 2020 and 30

more GW in construction

• US grew its civil nuclear program in

a short burst , slowed in 1979, and

today, a resurgence/ US developed

the PWR technology that is in use in

most of the world today

• Nuclear cooperation agreement

agreement approved by Congress in

1998, 13 years after proposed

Diablo Canyon, 2

Westinghouse PWRs

operating, U.S.

Sanmen 1, 1100 AP1000

PWR, under construction,

China

• U.S. and China are the largest consumers of energy

and producers of carbon dioxide

• China operates 11 nuclear power plants, representing 2

percent of electricity supply, and 14 units under

construction, and 10 planned to start construction this

year.

• The U.S. has 104 operating plants, 1 under construction

(TVA Watts Bar 2), 17 applications for 26 new plants

filed with NRC

• China technology provided initially by France and

Russia; US developed original PWR technology that

was exported to France and around the world

39

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