fhrs and the future of nuclear energy - uxc specific/smahtr...fhrs and the future of nuclear energy...
TRANSCRIPT
FHRs and the Future of Nuclear Energy
Presented to DOE FHR Workshop
At Oak Ridge National Laboratory Sept. 20-21, 2010
By Sherrell Greene Director, Nuclear Technology Programs Oak Ridge National Laboratory [email protected], 865.574.0626
2 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
Presentation Overview
• Nuclear energy success criteria – the Five Imperatives of Nuclear Energy
• FHR distinctives • FHRs as enablers of the Five
Imperatives of Nuclear Energy
3 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
April 2010 DOE Nuclear Energy Roadmap establishes four objectives Develop technologies and other
solutions that can improve the reliability, sustain the safety, and extend the life of current reactors
Develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration's energy security and climate change goals
Develop sustainable nuclear fuel cycles
Understand and minimize the risks of nuclear proliferation and terrorism
4 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
The Five Imperatives of Nuclear Energy define success
1. Extend life, improve performance, and sustain health and safety of the current fleet
2. Enable new plant builds and improve the affordability of nuclear energy
3. Enable the transition away from fossil fuels in the transportation and industrial sectors
4. Enable sustainable fuel cycles
5. Understand and minimizing proliferation risk
Abundant Nuclear Energy
5 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
FHR’s combine attributes and technologies of several different reactor types
MSRs
• Fluoride Salt Coolants
• Structural Materials • Pump Technologies
GCRs
• TRISO Fuels
• Structural Materials • Brayton Power Conversion
SFRs
• Low Primary Pressures
• Hot Refueling Technologies
LWRs
• Water/Air-tolerant Coolants
• Integral Primary Coolant Systems
FHRs
6 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
Four FHR concepts have been developed in U.S.
AHTR = Advanced High Temperature Rx PB-AHTR = Pebble Bed Advanced High Temperature Rx
HEER (1000 MWt)
PB-AHTR (410 MWe)*
SmAHTR (125 MWt / 50 MWe) HEER = High Efficiency and Environmentally Friendly Nuclear Rx SmAHTR = Small Modular Advanced High Temperature Rx
AHTR (1235 MWe)*
7 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
The potential benefits of FHRs stem directly from fundamental materials characteristics
Coolant
Tmelt (ºC)
Tboil (ºC)
Density (kg/m3)
Specific Heat
(kJ/kgºC)
Volumetric Heat
Capacity (kJ/m3ºC)
Thermal Conductivity
(W/mºC)
Kinematic Viscosity
(106m2/s)
Li2BeF4 (Flibe) 459 1430 1940 2.42 4670 1 2.9
59.5NaF-40.5ZrF4 500 1290 3140 1.17 3670 0.49 2.6
26LifF-37NaF-37ZrF4 436 2790 1.25 3500 0.53
31LiF-31NaF-38BeF2 315 1400 2000 2.04 4080 1 2.5
8NaF-92NaBF4 385 700 1750 1.51 2640 0.5 0.5
Sodium 97.8 883 82 1.27 1040 62 0.1
Lead 328 1750 10540 0.15 1700 18 0.1
Lead-Bismuth 125 1737 10000 0.14 1400 13 <0.1
Helium, 7.5 Mpa 3.8 5.2 20 0.29 11.0
Water, 7.5 Mpa 0 290 732 5.5 4040 0.56 0.1
8 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
The principal challenges of FHRs also stem from fundamental materials considerations
Coolant
Tmelt (ºC)
Tboil (ºC)
Density (kg/m3)
Specific Heat
(kJ/kgºC)
Volumetric Heat
Capacity (kJ/m3ºC)
Thermal Conductivity
(W/mºC)
Kinematic Viscosity
(106m2/s)
Li2BeF4 (Flibe) 459 1430 1940 2.42 4670 1 2.9
59.5NaF-40.5ZrF4 500 1290 3140 1.17 3670 0.49 2.6
26LifF-37NaF-37ZrF4 436 2790 1.25 3500 0.53
31LiF-31NaF-38BeF2 315 1400 2000 2.04 4080 1 2.5
8NaF-92NaBF4 385 700 1750 1.51 2640 0.5 0.5
Sodium 97.8 883 82 1.27 1040 62 0.1
Lead 328 1750 10540 0.15 1700 18 0.1
Lead-Bismuth 125 1737 10000 0.14 1400 13 <0.1
Helium, 7.5 Mpa 3.8 5.2 20 0.29 11.0
Water, 7.5 Mpa 0 290 732 5.5 4040 0.56 0.1
Design Challenges:
• High coolant mel6ng temperatures • Code-‐qualified compa6ble high temp. metals
• Maintenance of salt chemistry / purity • Wet refueling at high temperature
9 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
2004 ORNL analyses* indicate cost of large FHRs can be lower than GCR and SFR power systems
FHR Concept Frac5on of S-‐PRISM
Cost (1681 $/kWe)
Frac5on of GT-‐MHR Cost
(1528 $/kWe)
AHTR-‐IT (1145 MWe, 800 C Tcout)
.55 .61
AHTR-‐VT (1300 MWe, 1000 C Tcout)
.49 .53
* Ingersoll et al., “Status of Preconceptual Design of the Advanced High-Temperature Reactor (AHTR), ORNL/TM-2004/104, May 2004
Cost advantages: • Thin-‐walled vessels and piping • More compact reactor and primary coolant loops • Smaller confinement/containment systems • High opera6ng temperatures and thermal efficiencies
Abundant Nuclear Energy
10 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
Achievement of Imperative 3 depends on our success in delivering nuclear process heat for many applications
Abundant Nuclear Energy
11 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
Working temperatures of fluoride salts are well suited for variety of process heat applications
0 100 200 300 400 500 600 700 800 900 1000 110 1200 1300 1400 1500 1600 1700
Petro Refining
Oil Shale/Sand Processing
Cogeneration of Electricity and Steam
Steam Reforming of Nat. Gas & Biomass Gasification
Electrolysis, H2 Prod., Coal Gasification
NaF-BeF2 (57-43)
RbF-ZrF4 (58-42)
LiF-NaF-KF (46.5-11.5-42)
LiF-BeF2 (67-33)
NaF-ZrF4 (59.5-30.4)
Temperature (C)
Melts Boils
Abundant Nuclear Energy
12 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
FHR salt coolant heat transfer technologies were successfully demonstrated in MSRE for > 26,000 hr
Molten Salt Reactor Experiment (1965 – 1969)
600 ˚C LiF-BeF2 / Air Blast Radiator MSRE LiF-BeF2 Secondary Coolant Loop
Abundant Nuclear Energy
13 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
FHRs incorporate many attractive attributes for high-temperature process heat applications
Coolant (Reactor Concept)
High Working Tempa
High Volumetric
Heat Capacityb
Low Primary Pressurec
Low Reac5vity With Air & Waterd
Water (PWR) # # Sodium (SFR) #Helium (GCR) # # Salt (AHTR)
a FHR system working temperature functionally limited by structural materials capabilities b High coolant volumetric heat capacity enables constant temperature heat addition / removal (ηC = 1 – TC/TH ~ Carnot cycles), compact system architectures, and reduces pumping power requirements c Low primary system pressure reduces cost of primary vessel and piping, and reduces energetics of pipe break accidents d Low reactivity with air and water reduces energetics of pipe break accidents
Abundant Nuclear Energy
14 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
FHRs can implement or enable all three fuel cycle classes
• Once-Through – Standard once-through U
fuel cycle – similar to NGNP / GCR fuel cycles
– Once-through Th fuel cycle
• Modified Open – “Deep Burn” – similar to
deep burn gas reactor fuel cycle
– U-Th fuel cycles
• Full Recycle – Modified Open Cycle tier of
multi-tier Full Recycle
Abundant Nuclear Energy
15 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
FHRs have desirable non-proliferation attributes
• Qualitative comparative analysis: – Better than LWRs and SFRs
• TRISO fuel more difficult to reprocess than LWR and fast reactor fuels • FHRs have lower fissile inventory than SFRs
– Equivalent or better than gas cooled reactors • Similar TRISO fuel (U; Th; or Deep Burn U,Pu,Np) • Additional value of solidified salt coolant as barrier to fuel access?
• Systematic examination of FHR proliferation attributes is needed.
Abundant Nuclear Energy
16 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
FHRs show much promise as enablers of the Five Imperatives of Nuclear Energy
1. Extend life, improve performance, and sustain health and safety of the current fleet
2. Enable new plant builds and improve the affordability of nuclear energy
3. Enable transition away from fossil fuels in the transportation and industrial sectors
4. Enable sustainable fuel cycles
5. Understand and minimize proliferation risk
17 Managed by UT-Battelle for the U.S. Department of Energy
S. R. Greene, 20 Sept 10
Summary • FHRs show much promise as enablers of the Five
Imperatives of Nuclear Energy • Much work is needed • A balanced FHR R&D strategy is required
– System concept development should: • Identify optimal system architectures and technologies for differing
applications • Enable improved cost estimates • Enable fuel cycle and non-proliferation assessments • Inform technology and component R&D priorities
– FHR technology development should: • Address key base technologies: coolants, materials, fuels, and I&C • Address key component technologies: heat exchangers, pumps, valves • Leverage ongoing NGNP and GCR R&D