M. Abdou
3-24-03
Notes for Informal Discussion with Senior Fusion Leaders
in Japan (JAERI and Japanese Universities)
Outline
1.
Notes on US-35Yr Plan
2.
Why CTF in the US Plan
3.
Political situation for fusion and budget issues
4.
ITER organization in the US
5.
ITER Blanket Test Module (BTM)
- ITER plan for BTM and what it means
- R&D timing (EU rollback R&D plan)
- US-Japan Collaboration on BTM
- Collaboration with JAERI
- Collaboration with Japanese Universities (and Relationship
to JUPITER-II)
US 35-Yr Plan
•To put electricity from fusion on the US Grid in 35 years
•Charge from Dr. Ray Orbach, Director of the DOE Office of Science
•Panel had 19 members; Started October 2002
•Final Report (81 pages) submitted to FESAC; Accepted and Endorsed
Some Highlights of the Plan
•DEMO must be a “real” DEMO (50% availability, tritium self-sufficiency, etc.)
• Ferritic steel is the only realistic structural material for DEMO
•Portfolio of both IFE&MFE with selection in 2019
•MFE Portfolio has ITER, IFMIF, and CTF
•International collaboration assumed on ITER and IFMIF and other activities
•Total cost of the plan is $24B
- The US contribution to ITER construction was assumed to be $1B
- The US contribution to IFMIF is about 25%
- The US is willing to pay the full cost for CTF (MFE) [or ETF for IFE]
NIF and ITER Drive the Urgency of the Plan
NIF
ITER
A strong parallel effort in the science and
technology of fusion energy is required to guide
research on these experimental facilities and to
take advantage of their outcome.
Fiscal Year 03
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Theory, Simulation and Basic Plasma Science
Configuration
Configuration Optimization
Optimization
Concept Exploration/Proof of Principle
IFE IREs
Key Decisions:
IFE IREs
Design
MFE PE Exp’ts
Construction
Burning Plasma
Operation
IFE NIF
MFE PEs
Indirect Drive
Direct Drive
ITER Phase II
MFE ITER (or FIRE)
IFMIF
Materials Testing
Materials Science/Development
MFE or IFE
First Run
Second Run
IFMIF
Demo
Component Testing
Engineering Science/ Technology Development
IFE ETF
MFE CTF
Demonstration
Systems Analysis / Design Studies
US Demo
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Fiscal Year 03
MFE Detail and
Dependencies
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Theory, Simulation and Basic Plasma Science
Configuration
Optimization
Concept Exploration
Configuration
Optimization
MST & NSTX
NCSX
New POP’s
Design
Existing MFE PE Exp’ts
Key Decisions:
Construction
1st New MFE PE
2nd New MFE PE
Operation
MFE PEs
Burning Plasma
IFMIF
MFE or IFE
ITER Phase II
MFE ITER (or FIRE)
Materials Testing
Materials Science/Development
Demo
First Run
Second Run
IFMIF
Component Testing
Engineering Science/ Technology Development
MFE CTF
Demonstration
Systems Analysis / Design Studies
US Demo
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The Administration on Fusion
“This [progress in fusion science] is an enormous change that is enough to change the
attitudes of nations toward the investments required to bring fusion devices into
practical application and power generation.”
Presidential Science Advisor John Marburger
“By the time our young children reach middle age, fusion may begin to deliver energy
independence … and energy abundance …to all nations rich and poor. Fusion is a
promise for the future we must not ignore. But let me be clear, our decision to join
ITER in no way means a lesser role for the fusion programs we undertake here at
home. It is imperative that we maintain and enhance our strong domestic research
program … . Critical science needs to be done in the U.S., in parallel with ITER, to
strengthen our competitive position in fusion technology.”
Secretary of Energy, Spencer Abraham
“The results of ITER will advance the effort to produce clean, safe, renewable, and
commercially-available fusion energy by the middle of this century.
Commercialization of fusion has the potential to dramatically improve America’s
energy security while significantly reducing air pollution and emissions of greenhouse
gases.”
President George W. Bush
Political Support and Budget Issues for Fusion in the US
• Good News
- Strong statements from President Bush and Secretary of Energy
• Join ITER & Develop Fusion Energy
- 35-Yr Plan widely supported by the fusion community
• Concerns: Budget! Budget! Budget!
- The Budget reality does not match the Presidential Policy
- FY03 came from Congress as $250M ($7M less than the President’s request)
- FY04 President’s Budget Submission
• Only $257M (no increase)
• Deep and disturbing cuts in Fusion Technology (Draconian cuts)
• Other Major Concerns:
- Two camps in the Administration. One camp wants fusion to focus
only on Plasma Science. The other camp wants fusion energy.
Fusion Budget Problem is Worldwide?
• The US Fusion Budget problems are not unique
• Similar problems in EU, in Japan?
• Problem: Political commitment is not strong enough to be
reflected in budgets!!
One Necessary Measure (Personal View)
- We must enhance international collaborations
- We must increase effectiveness of domestic programs and
international collaboration
The US has now joined ITER Negotiations (also China)
ITER Organization in the US
For Now
• An ITER Project Office at PPPL
Director: Ned Sauthoff (C. Baker, Deputy)
• BP-PAC (Burning Plasma Program Advisory Committee)
- Will provide guidance (technical and organizational)
- Includes 10 people from Universities, Labs, and Industry
• Mike Roberts will be OFES Manager responsible for ITER
For the Long-Term
• Organization will evolve and become more formal
ITER Operational Plan Calls for Testing Breeding
Blankets from Day 1 of Operation
H-Plasma Phase
D Phase
First DT plasma phase
Accumulated
fluence =
0.09 MWa/m2
Blanket
Test
TBM Roll Back from ITER 1st Plasma
Shows CT R&D must be accelerated now for TBM Selection in
EU schedule for Helium-Cooled
Pebble Bed TBM (1 of 4 TBMs Planned)
02 03 04 05 06 07 08 09 10 11 12
2005
ITER First Plasma
13 14 15 16 17 18 19 20 21 22 23 24 25
HCPB Programme
PB Material Fabrication and
Char. (mech., chem, etc)
Out-of-pile pebble bed
experiments
Pebble bed Irradiation
Programme
Modelling on Pebble beds
including irradiation effects
Key issues of Blanket
Structure Fabr. Tech.
HCPB Programme for ITER
Develop. and testing of
instrumentation for TBM
Develop. and testing of
components of Ext. Loops
TBM and Ext. Loop Mock-up
Design
TBM and Ext. Loops Mock-up
Fabrication
Operation of TBM and Ext.
Loop Mock-ups
a final decision on blanket test
modules selection by 2005 in order
to initiate design, fabrication and
out-of-pile testing
Final Design of TBM
Fabrication and qualification of
TBM and Ext. Loops
Operation in the Basic
Performance Phase of ITER
(Reference: S. Malang, L.V. Boccaccini, ANNEX 2, "EFDA Technology Workprogramme 2002 Field: Tritium
Breeding and Materials 2002 activities- Task Area: Breeding Blanket (HCPB), Sep. 2000)
ITER Test Program US-Japan Collaboration
(Ferritic Steel is the Reference DEMO material worldwide)
Blanket Options for ITER Blanket Test Module (BTM)
1) Solid Breeder Blankets
– Common Interest in EU, Japan, and US
– Collaboration between US and JAERI
– Some limited activity under JUPITER-II (Task 2.2)
2) Molten Salt Self-Cooled Concept
– Some activity under JUPITER-II
– Is it a candidate for ITER TBM?
3) Liquid Metal Blanket Concepts
– Self-cooled Li/V concept
– Helium-cooled Pb-17Li concept
– Helium-cooled Pb-17Li concept with SiC insert
Main Critical Issues
Common to all concepts:
- tritium self-sufficiency
- ferromagnetic effects
- forces and stresses caused by disruptions
- reliability of blanket/First Wall/divertor
Specific to helium-cooled Pb-17Li concepts:
- tritium permeation and control, corrosion
- SiC insert compatibility and performance integrity
Specific to self-cooled Li concept:
- coating development and crack tolerance
- MHD effects
- tritium recovery and control
Specific to molten salt concept:
- redox, tritium recovery and control, Be toxicity
- enhancing Heat Transfer
Specific to solid breeder blanket concepts:
- effective thermal conductivity and interface thermal conductance
- irradiation effect on beryllium, tritium inventory in Be
- high burn up effect on ceramic breeder materials
- tritium control
ITER Test Program US-Japan Collaboration
Questions
1) If each party is allowed only to test two blanket concepts:
a) What are the two favored concepts in Japan? And in US?
b) What are the mechanisms in the US and in Japan to arrive at these
decisions?
c) Should we have joint study/assessments to try to arrive at common
concepts to maximize the utilization of limited resources/budgets in
both countries?
2) Should the US have collaboration with JAERI separate from
collaboration with Japanese Universities?
a) How do we enhance US-JAERI collaboration?
b) Should we orient JUPITER-II to serve collaboration between US and
Japanese Universities on ITER BTM?
CTF
CTF
 Component Test Facility
 Chamber Technology Facility
 New Name for VNS
• CTF is included in the US Plan as a Necessary Facility prior to
DEMO
• For detailed information on Why CTF Is Needed:
1) Presentation by M. Abdou (e.g. Seminar at MIT is on cd)
2) See paper-- “Results of an International Study on a HighVolume Plasma-Based Neutron Source for Fusion Blanket
Development,” Fusion Technology, 29: 1-57 (1996) by M.
Abdou, et.al
• Note that Component Testing is NECESSARY in all Engineering
Development. (It is not just material development.)
What is CTF?
CTF  Component Test Facility (or Chamber Technology Facility)
(CTF is a new name for VNS)
• The idea of CTF is to build a small size, low fusion power
DT plasma-based device in which Fusion Nuclear
Technology experiments can be performed in the relevant
fusion environment at the smallest possible scale, cost,
and risk.
- In MFE: small-size, low fusion power can be obtained in a low-Q
plasma device.
- Equivalent in IFE: reduced target yield and smaller chamber radius
• This is a faster, much less expensive, lower-risk
approach than testing in a large, ignited/high Q plasma
device for which tritium consumption, and cost of
operating to high fluence are very high (unaffordable!,
not practical).
Critical R&D Issues for Chamber Technology (FNT)
1.
2.
3.
Remaining Engineering Feasibility Issues, e.g.
• feasibility, reliability and MHD crack tolerance of electric insulators
• tritium permeation barriers and tritium control
• tritium extraction and inventory in the solid/liquid breeders
• thermomechanics interactions of material systems
• materials interactions and compatibility
• synergistic effects and response to transients
D-T fuel cycle tritium self-sufficiency in a practical system
depends on many physics and engineering parameters/details: e.g. fractional
burn-up in plasma, tritium inventories, FW thickness, penetrations, passive
coils, and many more variables. A related issue is how to supply Tritium for
burning plasma experiments, such as ITER.
Reliability/Maintainability/Availability: failure modes, effects, and
rates in blankets and PFC’s under nuclear/thermal/mechanical/electrical/
magnetic/integrated loadings with high temperature and stress gradients.
Maintainability with acceptable shutdown time.
4.
Lifetime of blanket, PFC, and other FNT components
Stages of FNT Testing in Fusion Facilities
Fusion
“Break-in”
Stage:
Required
Fluence
2
(MW-y/m )
Size of Test
Article
I
~ 0.3
SubModules
• Initial exploration of
performance in a fusion
environment
• Calibrate non-fusion tests
• Effects of rapid changes in
properties in early life
• Initial check of codes and data
• Develop experimental
techniques and test
instrumentation
Design Concept
& Performance
Verification
Component Engineering
Development &
Reliability Growth
II
III
1-3
>4-6
Modules
Modules
/ Sectors
• Tests for basic functions and
phenomena (tritium release / recovery,
etc.), interactions of materials,
configurations
• Verify performance beyond beginning
of life and until changes in properties
become small (changes are substantial
2
up to ~ 1-2 MW · y/m )
• Data on initial failure modes and
effects
• Narrow material combination
and design concepts
• Establish engineering feasibility of
blankets (satisfy basic functions &
performance, 10 to 20% of lifetime)
• 10-20 test campaigns, each is 12 weeks
• Select 2 or 3 concepts for further
development
• Identify failure modes and effects
• Iterative design / test / fail / analyze /
improve programs aimed at
improving reliability and safety
• Failure rate data: Develop a data
base sufficient to predict mean-timebetween-failure with sufficient
confidence
• Obtain data to predict mean-time-toreplace (MTTR) for both planned
outage and random failure
• Develop a data base to predict
overall availability of FNT
components in DEMO
D
E
M
O
Critical Factors in Blanket / PFC / FNT
Testing that Make CTF a Necessary
Facility in Fusion Energy Development
Pathway Toward Demo
• Tritium Consumption / Supply Issue
• Reliability / Maintainability / Availability
Issue
• Cost
• Risk
• Schedule
Fundamental Considerations in Blanket / PFC / FNT
Fusion Testing that Make CTF Necessary
• The FNT Testing Requirements are
Fusion Power only 20-30 MW
Over about 10m2 of surface area (with exposure to plasma)
With Steady State Plasma Operation (or plasma cycle >80%)
Testing Time on successive test articles equivalent to neutron fluence of 6
MW • y/m2
• Tritium Consumption / Tritium Supply issue dictates that any fusion facility that performs
FNT testing must internally breed all (or most) of its own tritium
- If TBR <1, Larger Power Devices require larger TBR
- For a given TBR, the FW area required for breeding is much larger than for small
devices
• FNT Testing involves RISKS to the fusion testing device
- unvalidated technology with direct exposure to plasma
- frequent failures are expected
- considerable amounts of tritium and activated materials
- These risks are much greater for large power devices because of the much
larger area for tritium breeding
• Cost
- Frequent failures will require frequent replacements: COST will be much higher for
the larger power, larger area devices
- COST of operation to higher fluence is larger for larger devices
CTF MISSION is integrated testing and development of fusion power and
fuel cycle technologies (FNT) in prototypical fusion power conditions
Scope of Testing in CTF
 Information Obtained from
Basic Device
– Divertor Operation
– Heating and Current Drive
Systems PFC
– Partial to full breeding, high
temperature blanket (staged
operation and breeding)
– Neutronics and Shielding
– Tritium Fuel Cycle
 Demonstration of Remote
Maintenance Operations
– through frequent changeout
of various test articles
– through repairs and
changeout on the basic
device
 Testing in Specialized Test
Ports (and substantial FW
coverage at later stages of
operation)
– Materials Test Module
• Material Properties Specimen
matrix
– Blanket Test Modules
• Screening Tests
• Performance Verification
• Reliability Growth
– Divertor Test Modules
• Engineering Performance
• Design Improvements and
Advanced Divertor Testing
– Current Drive and Heating Launchers
– Neutronics Test Sector
– Safety Aspects of the Test Program
– Tritium Processing
Tritium Consumption in Large and Small Power DT Devices
AND Tritium Supply Issue
AND Impact on the Path to FNT Development
Note: Projections of world tritium supply available to fusion for various scenarios were
generated by Scott Willms, including information from Paul Rutherford’s 1998 memo
on “Tritium Window”, and input from M. Abdou and D. Sze.
Projected Ontario (OPG) Tritium
Inventory (kg)
Projections for World Tritium Supply Potentially
Available to Fusion
30
25
Candu Supply
20
w/o Fusion
15
10
5
0
1995
2000
2005
2010
2015
2020
2025
2030
2035
2040
2045
Year
• World Maximum Tritium Supply (mainly CANDU) available for fusion is 27 kg
• Tritium Consumption in a DT facility burns tritium at a rate of 55.8 kg/yr per 1000
MW of fusion power
• Tritium decays at a rate of 5.47% yr
• Current Tritium cost is $30 million/kg
• Once the Canadian Tritium is gone, additional tritium may be produced at a
projected cost of $200 million/kg (estimate by Anderson, Wittenberg, Willms, & Sze)
Conclusion
A large power DT facility must breed its own tritium
Separate Devices for Burning Plasma and FNT Development, i.e.
ITER (FEAT) + CTF is more Cost Effective and Faster than a
Single Combined Device
(to change ITER design to satisfy FNT testing requirements is very
expensive and not practical)
NWL
Fusion
Power
Fluence
(MW·y/m2)
Tritium
Consumption
(TBR = 0)
Tritium
Consumption
(TBR = 0.6)
0.55
500 MW
0.1
5 kg
2 kg
2) FNT Testing (CTF)
>1
< 100 MW
>6
33 kg
13 kg
Single Device Scenario
(Combined Burning Plasma +
FNT Testing), i.e. ITER with
major modifications (double the
capital cost)
>1
910 MW
>6
>305 kg
>122 kg
Two Device Scenario
1) Burning Plasma (ITER)
FACTS
- World Maximum Tritium Supply (mainly CANDU) available for Fusion is 27 kg
- Tritium decays at 5.47% per year
- Tritium cost now is $30M / kg. More tritium will cost $200M / kg.
Conclusion:
- There is no external tritium supply to do FNT testing development in a large power
DT fusion device. FNT development must be in a small fusion power device.
Projected Ontario (OPG) Tritium Inventory (kg)
The Lack of Adequate Tritium Supply and the Need for Tritium Breeding
Blanket are Already Having a Major Impact NOW on ITER Operational
Plans and Fusion Energy Development Plans
30
CTF
5 yr, 100 MW, 20% Avail, TBR 0.6
5 yr, 120 MW, 30% Avail, TBR 1.15
10 yr, 150 MW, 30% Avail, TBR 1.3
25
20
Candu Supply
w/o Fusion
15
1000 MW Fusion,
10% Avail, TBR 0.0
ITER-FEAT (2004
start) + CTF
10
5
0
1995
ITER-FEAT
(2004 start)
See calculation assumptions in
Table S/Z
2000
2005
2010
2015
2020
Year
2025
2030
2035
2040
2045
• World Tritium Supply would be Exhausted by 2025 if ITER were to run at 1000 MW fusion power
with 10% availability without tritium breeding capability.
• Large Power DT Fusion Devices are not practical for blanket/PFC development.
• Blanket/PFC must be developed prior to DEMO (and we cannot wait very long for
blanket/PFC development even if we want to delay DEMO).
• CTF is a critical facility for fusion energy development.
Reliability / Maintainability / Availability
Critical Development Issues
Unavailability = U(total) = U(scheduled) + U(unscheduled)
This you design for
This can kill your DEMO and your future
Scheduled Outage:
Planned outage (e.g. scheduled maintenance of components, scheduled
replacement of components, e.g. first wall at the end of life, etc.).
This tends to be manageable because you can plan scheduled maintenance /
replacement operations to occur simultaneously in the same time period.
Unscheduled Outage: (This is a very challenging problem)
Failures do occur in any engineering system. Since they are random they tend
to have the most serious impact on availability.
This is why “reliability/availability analysis,” reliability testing, and
“reliability growth” programs are key elements in any engineering
development.
Availability (Due to Unscheduled Events)
1
i represents a component
Availability: =
1   Outage Risk
i
(Outage Risk) i = (failure rate) i • (mean time to repair) i=
MTTR i
MTBFi
MTBF = mean time between failures = 1/failure rate
MTTR = mean time to repair
• A Practical Engineering System must have:
1. Long MTBF: have sufficient reliability
- MTBF depends on reliability of components.
One can estimate what MTBF is NEEDED from “availability allocation
models” for a given availability goal and for given (assumed) MTTR.
But predicting what MTBF is ACHIEVEABLE requires real data
from integrated tests in the fusion environment.
2. Short MTTR: be able to recover from failure in a short time
- MTTR depends on the complexity and characteristics of the system (e.g.
confinement configurations, component blanket design and configuration,
nature of failure). Can estimate, but need to demonstrate MTTR in fusion
test facility.
The reliability requirements on the Blanket/FW (in current confinement concepts that
have long MTTR > 1 week) are most challenging and pose critical concerns. These must
be seriously addressed as an integral part of the R&D pathway to DEMO. Impact on
ITER is predicted to be serious. It is a DRIVER for CTF.
800
ed
(R
)
600
5
400
200
0
Expected
0
1
2
C
A
0
3
MTBF per Blanket Segment(FPY)
10
N
ee
d
MTBF per Blanket System(FPY)
The Chamber Technology Program NOW is
leading the way to resolving this challenge.
MTTR (Months)
A = Expected with extensive R&D (based on mature technology and no fusion-specific failure modes)
C = Potential improvements with aggressive R&D
Reliability/Availability is a challenge to fusion,
particularly blanket/PFC, development
• Fusion System has many major components (TFC, PFC, plasma heating,
vacuum vessel, blanket, divertor, tritium system, fueling, etc.)
- Each component is required to have high availability
• All systems except the reactor core (blanket/PFC) will have reliability data
from ITER and other facilities
• There is NO data for blanket/PFC (we do not even know if any present blanket
concept is feasible)
• Estimates using available data from fission and aerospace for unit failure rates
and using the surface area of a tokamak show:
PROBABLE MTBF for Blanket ~ 0.01 to 0.2 yr
compared to REQUIRED MTBF of many years
Aggressive “Reliability Growth” Program
We must have an aggressive “reliability growth” program for the
blanket / PFC (beyond demonstrating engineering feasibility)
1) All new technologies go through a reliability growth program
2) Must be “aggressive” because extrapolation from other technologies
(e.g. fission) strongly indicates we have a serious CHALLENGE
“Reliability Growth”
Upper statistical confidence level as a function of test time in
multiples of MTBF for time terminated reliability tests (Poisson
distribution). Results are given for different numbers of failures.
1.0
Number of Failures 0
Confidence Level
0.8
Example,
TYPICAL
TEST
SCENARIO
1
To get 80% confidence
in achieving a particular
value for MTBF, the
total test time needed
is about 3 MTBF (for
case with only one
failure occurring during
the test).
2
0.6
3
0.4
4
0.2
0.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Test Time in Multiplies of Mean-Time-Betw een-Failure (MTBF)
Reference: M. Abdou et. al., "FINESSE A Study of the Issues, Experiments and Facilities for Fusion Nuclear
Technology Research & Development, Chapter 15 (Figure 15.2-2.) Reliability Development Testing Impact on Fusion
Reactor Availability", Interim Report, Vol. IV, PPG-821, UCLA,1984. It originated from A. Coppola, "Bayesian
Reliability Tests are Practical", RADC-TR-81-106, July 1981.
DEMO reactor availability obtainable with 80% confidence
for different testing scenarios, MTTR = 1 month
DEMO Reactor Availability
0.3
0.2
MTTR = 1 month
12 test modules
1 failure during the test
Experience factor =0.8
III: ITER +VNS
0.492
This assumes that the
divertor has availability
similar to blanket system
availability, & that
combined availability of all
other major Demo
components
= 60%
II: ITER BPP
+VNS
0.360
IV: ITER +
delayed VNS
0.1
0.189
I: ITER only
0.0
2006
2013
2010
2014
2018
2022
2026
2017
2021
2025
2029
2033
Blanket System Availability
0.654
0.4
(Schedule back
2030 in 1995)
2037
(Schedule now
in 2002)
Calendar year
Note: ITER in Scenarios I, III and IV assumes fluence of 1.1 MWy/m2
(ITER-FEAT 1st phase has 0.1 MWy/m2)
Conclusions on Blanket and PFC Reliability Growth
• Blanket and PFC tests in ITER alone cannot demonstrate DEMO
availability higher than 4%
(This also assumes ITER would be modified to a higher wall load
and to operate with steady state plasma)
• Blanket and PFC testing in VNS (CTF) allows DEMO blanket system
and PFC system availability of > 50%, corresponding to DEMO
availability > 30%
Note that testing time required to improve reliability becomes even longer at higher
availability [e.g. testing time required to increase availability from 30% to 50% is much
longer than that needed to improve availability to 30%]
Recommendations on Availability/Reliability Growth Strategy and Goals
- Set availability goal for initial operation of DEMO of ~ 30% (i.e. defer some risk)
- Operate CTF and ITER in parallel, together with other facilities, as aggressively
as possible
- Realize that there is a serious decision point with serious consequences based
on results from ITER and CTF
• If results are positive proceed with DEMO
• If not, then we have to go back to the drawing board
Are there Good Design Options for CTF?
• A key point in the rationale behind CTF is to design a small
size, small fusion power (~100 MW), yet achieve a high
neutron wall load and steady state plasma operation.
• This can be achieved in MFE by using highly driven plasma
(low-Q plasma ~ 1-2).
[Similar idea in IFE is to use low target-yield to lower the fusion
power but make the chamber radius small enough to get
higher wall load]
• Several good options for CTF look attractive.
• The fusion physics and engineering communities need to jointly
explore in more detail the options for CTF:
e.g. - ST, low-A, standard-A
- physics and engineering details