Findings of the FESAC subpanel on Transformative
Enabling Capabilities (TEC)

Panel Leads: R. Maingi, A. Lumsdaine
Panelists: J.P. Allain, L. Chacon, S. Gourlay, C. Greenfield, J. Hughes,
D. Humphreys, V. Izzo, H. McLean, J. Menard, B. Merrill, J. Rapp, O. Schmitz,
C. Spadaccini, Z. Wang, A. White, B. WirthEx-officio: D. Rej (FESAC chair), S. Knowlton (FESAC co-chair)
FES contact: S. Barish
FESAC debriefing
Gaithersburg, MD
Feb. 1, 2017

Summary• Charge: identify promising Transformative Enabling
Capabilities “that could promote efficient advance toward
fusion energy, building on burning plasma science andtechnology.”• Panel formed in Feb./March 2017
– Representatives from Labs, Universities, Industry– Expertise covered range of key technological areas• Community input via talks (3 meetings) and white papers– 67 Talks and 67 White papers– Face to face and ZOOM meetings• Findings: Four Tier 1 TECs (not prioritized), one Tier 2 TEC– Foundational and Enabling Activities• Draft report sent informally to FESAC members and a few
community leaders 1/17/18– Thank you! We incorporated feedback to extent possible
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Working definition of Transformative Enabling
Capability (TEC)• A TEC is a “game-changing” idea, toward revolutionary andbeyond evolutionary• A TEC would dramatically increase the rate of progress
towards a fusion power plant– Does not have to be a new idea, but can be one where rapid pace ofprogress is driven by other fields– We have grouped several exciting technologies to form the TECs
that are presented in the report

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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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Charge• The FESAC was recently charged “to identify themost promising transformative enabling capabilities
for the U.S. to pursue that could promote efficientadvance toward fusion energy, building on burning
plasma science and technology.”• The charge lists sample focus areas including ”liquid
metals, additive manufacturing, high criticaltemperature superconductors, exascale computing,materials by design, machine learning and artificial
intelligence, and novel measurements.”– Note that these were examples– The committee accepted community input on any ”promisingtransformative enabling capabilities” that promote efficientadvance toward fusion energy
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Charge Note and Panel breakdown• Note that this activity is an assessment of (multiple) technicalcapabilities, and not an evaluation of confinement devices.
According to the charge “Identification of R&D that may havegeneral impact that both includes and extends beyond” tokamak
and stellarator concepts “is welcome. However an assessmentof various types of confinement devices is not to be performed.”• The TEC subcommittee (R. Maingi, Chair, and A. Lumsdaine,
Vice-Chair, full membership listed below) was sub-divided into
three sub-panels corresponding to different areas of technology
application:– Plasma Diagnostics, Actuators, and Control– Plasma Materials Interaction– Reactor and Balance of Plant

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TEC Panel membership (1 of 2)• Rajesh Maingi* (PPPL) & Arnie Lumsdaine* – Chair andVice-Chair• Don Rej* (LANL) & Steve Knowlton* (Auburn – emeritus)– FESAC ex-officio members• Sam Barish (FES) – FES liaison• Plasma Materials Interaction (Material science andengineering)– Jean-Paul Allain (U. Illinois) – sub-panel lead
– Juergen Rapp* (ORNL)– Oliver Schmitz (UW-M)– Chris Spadaccini (LLNL)– Zhehui (Jeff) Wang (LANL)– Brian Wirth* (UT-K)* FESAC members
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TEC Panel membership (2 of 2)• Plasma Diagnostics, Actuators, and Control (Physics
and computation)– Anne White* (MIT) – sub-panel lead
– Luis Chacon (LANL)– Steve Gourlay (LBNL)– David Humphreys (GA)– Val Izzo (UCSD)• Reactor and Balance of Plant (Mechanical, electrical,
and nuclear engineering)– Charles Greenfield* (GA) – sub-panel lead
– Jerry Hughes (MIT)– Harry McLean (LLNL)– Jon Menard (PPPL)– Brad Merrill (INL)* FESAC members

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Previous reports and Community input details• In addition to ReNeW, other recent reports used:– 2007 Greenwald panel report– 2012 FESAC report and white papers on “Materials Science andTechnology Research Opportunities Now and in the ITER Era”
– 2012 Fusion Nuclear Science Pathways Assessment report(PPPL)– 2013 FESAC report and white papers on “Prioritization of
Proposed Scientific User Facilities for the Office of Science”– 2014 FESAC report and white papers on “Strategic Planning”– 2015 Community Workshop reports• Community submitted 67 White papers and presented
67 talks at the three meetings

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Community Input Meetings – Panel Q/A Sessions
Three meetings were conducted for community input:
ü May 30-June 1, 2017 (Rockville, MD): Community input
meeting for Plasma Diagnostics, Actuators, and Control subpanel, and also for Reactor and Balance of Plant sub-panel
ü June 20-22, 2017 (Chicago, IL): Community input meeting for
Plasma-Materials Interaction sub-panel
ü July 19-21, 2017 (PPPL, Princeton NJ): Final workshop for all
three sub-panels; one day of community input time

• Panel face-to-face on Sept. 6, 2017 (Gaithersburg, MD)

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Working definition of Transformative Enabling
Capability (TEC)• A TEC is a revolutionary idea, beyond evolutionary; it is a“game-changer”. A TEC would dramatically increase therate of progress towards a fusion power plant.
– Examples include a substantial increase in fusion performance,
enabling device simplification, reduction in fusion system cost or
time to delivery, or improvement in reliability and/or safety.
– In some cases innovations are needed in other areas to fully
capitalize on certain TECs.

• Two tiers of TECs were identified:– Tier 1: the capability is advancing rapidly e.g. as driven by otherfields, and/or the reward/risk ratio is clearly favorable; these are
evaluated as very promising TECs.
– Tier 2: the transformative potential is evident, but risks are more
substantial, and/or the rewards may be more difficult to quantify;these are evaluated as promising TECs.
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Evaluation Criteria• The charge asked to “comment on the promise, level ofmaturity, development requirements, risks and uncertainties,
and time horizon” and to “consider global strengths and gaps
in identifying areas of particular opportunity for the U.S.”• In the call for white papers, authors were asked to addresseach of these issues.
• The subcommittee used a metric (as a guideline) whenevaluating the various technologies and capabilities. This
included consideration of:– Transformative impact (as compared to current conventional
technology)– Risks and uncertainties– Maturity and development (Technical Readiness Levels – TRLs)– Broader impact
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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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Advanced Algorithms• Advanced algorithms will transform our vision of feedback
control of a power-producing fusion reactor from one ofbasic feasibility to one employing intelligent systems,
enabling operation at optimized points whose achievement
and sustainment are otherwise impossible– TEC includes: mathematical control, machine learning,
artificial intelligence, integrated data analysis– Mathematical control: solutions that establish the viabilityof fusion reactor operation will become within reach– Machine learning & AI: enable control of fusion plasmas
by bridging gaps in understanding of plasma dynamics– Availability of exascale computing will advance highfidelity and control-level modeling of plasma processes
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Advanced Algorithms Background• Control mathematics provides methods
to access optimized and robustly stable
plasma operating states (with sufficient
but not necessarily complete physics
models): virtually all aspects of operating
tokamaks are now enabled bysophisticated controls• Machine learning and AI can generate
useful models and effective controllers tobridge (small) gaps in physics
knowledge: cars drive themselves
without explicit knowledge of dynamics
behind behavior of other cars andpedestrians
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Technology Assessment for Mathematical Control• History and Status:– Control advancements have been a key source of transformational
breakthroughs that enable new technologies:• Heavier-than-air-flight, complex industrial processes, driverless cars

– Mathematical control key to advanced fusion device feedback control• Promise:– Advancement of mathematical control design for fusion will accelerate
physics understanding and enable sustained achievement of optimized
reactor regimes– Connections between control-mathematics experts and the fusion
community can accelerate progress• Risk and Uncertainty:– Potential for insufficient matching research to produce needed physics
models for control development and application

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Technology Assessment for Machine Learning and AI• History and Status:– Machine learning (ML) and AI are relatively new fields energized byadvances in computational capabilities and nonlinear mathematics– Recent advances have leaped from limited human-programmed vehicles tofully autonomous commercial cars and trucks in 20 years• Promise:– ML and AI offer methods for generating useful models and effective
controllers even in the presence of gaps in physics knowledge– Fields offer potential for extracting explicit physics understanding from verylarge collections of data

• Risk and Uncertainty:– Potential for insufficiently effective connection between fusion
community and ML community for new tools and methods– Potential for insufficient connection between fusion high performancecomputing community/research and ML/AI communities and research
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Technology Assessment for Offline and Real-time Data
Handling Algorithms• History and Status:– Integrated Data Analysis (IDA) and high-speed simulation are relatively
new fields made possible by recent advances in computational
capabilities, networks, and embedded systems– Integration of multiple data sources accomplished by hand, now
dramatically expanded to large-scale and automated data integration(impossible by hand)• Promise:– Systematic methods for offline and real-time data handling have potential
to transform data quality and accelerate physics understanding for fusion– IDA can aid in extracting explicit physics understanding from very large
collections of data, enhance confidence, and support verification andvalidation• Risk and Uncertainty:– Potential for insufficiently applying systematic data methods to derive
benefits
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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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High critical-temperature superconductors• Advances in higher critical temperature and/or higher field
superconductors present a game changing opportunity toenhance the performance and feasibility of reactor designs– SC magnets are the essential enabling technology for magnetic
confinement fusion– Advantages for designing fusion reactors with high magnetic fields– Transformative potential comes from the ability to achieve magnetic
fields well beyond currently available technology, potentiallyreducing the time and cost for fusion science research toward power
generation– Higher magnetic fields could result in more compact burning plasma
experiments– Operation at temperatures higher than conventional low temperature
superconductors raises the prospect of using demountable magnetic
field joints
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High critical-temperature superconductors backgroundTwo primary HTS materials with sufficient maturity• REBCO tapes (main focus for Fusion)– Current densities an order of magnitude
higher than LTS– Has achieved fields over 40 T in solenoids(2x over target for high field designs)– No heat treatment required– Good strain properties• Bi-2212 round strands– High current density– High current cable– Complex heat treatment– Strain sensitive– Possible use in pulsed systems
FESAC debriefing: TEC panel findings

Operating temps at 20 – 30K
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REBCO Technology Assessment - Promise• Present performance of commercially available REBCO
tape is already sufficient for use in practical fusion
experimental devices• High operating temperature and low sensitivity of criticalcurrent to temperature will lead to greater magnet operatingstability• Remains superconducting at high stresses, over 600 Mpa,
and strains up to 0.45%; 2-3x better than LTS• Initial radiation sensitivity comparable to Nb-Ti and Nb3Sn• Since remaining work is engineering rather than basic R&D,
an aggressive focused program could produce a prototype
magnet in less than a decade– Strong synergy with HEP magnet technology in key areas
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REBCO Technology Assessment - Challenges
•
•
•
•
•
•

Tape is natural for pancake coils but more complex
geometries need development.
Long lengths of conductor now produced but high current
cables using multi-tapes are still in prototype stages
Quench detection and protection of HTS magnets
Compact device could increase technical challenges inplasma exhaustHigh COST (Currently between $400 – 500/kA-m) –targeting $10/kA-m
LBNL 17-strand Rutherford cable
Significant cost reduction through a combination of– Increased production levels– Performance improvement (several programs in active pursuit)– Current sharing cables mitigate piece length limitations and reduce
cost
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Demountable Joints Technology Assessment• High thermal margin of HTS allows demountable joints– Vertical maintenance, simplification of installation andcomponent replacement– Use of demountable joints would broaden design options• Acceptable joint resistances have been demonstrated but
needs more experimental work
– Technology is fusion-specific; few external drivers• A reasonable first demonstration would be to operate asuperconducting coil at full field with low heat generation– Most required infrastructure already exists– Little global development gives US opening for leadership
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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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Advanced Materials• New material design and processes (i.e. “advanced andadditive manufacturing”) enable realization of resilient PFC
and structural materials components that are essential inharsh fusion reactor environment• Promising advances in advanced manufacturing (e.g. spark
plasma processing) and additive manufacturing are enablingnovel hierarchical material composites resulting in multifunctional materials for harsh environments• This TEC includes– Materials-by-design– Emergent fusion nuclear materials– Divertor materials– Complex heat transfer systems
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Advanced Materials –Challenges• Heatflux

Tungsten• Neutrons& He

14 MeV, high He/dpa
up to 150 dpa for blankets
up to 50 dpa for divertor• Surfaceevolution

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Additive manufacturing can revolutionize materials andcomponents for fusion energy reactors• Promise– Ability to fabricate highly complex structures– Control of microstructure for unique local
properties– Rapid design-fabricate-test cycles– Ability to fabricate with refractory metals suchas W, and other materials e.g. ODS steel– Widespread development community
A complex laEce structure made of 316SS
using an AM machine at LLNL.

• Risk– Technology for fusion relevant materials very
basic, unknown PMI and structural properties– Material properties can be different than
traditional materials despite being same alloy– Qualification of materials and components
can be more complex and expensive
FESAC debriefing: TEC panel findings

EBSD image of a nickel-based alloy showing
designed microstructure orienta;on createdby an AM machine at ORNL.

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Advanced materials – Materials by Design• Materials-by-design (MBD) combines predictive computational tools(e.g. machine-learning with robust advanced manufacturing) andsynthesis approaches, such Additive Manufacturing (AM)– Promise: design of complex components and geometries, theability to work with relevant materials such as refractory metals,
and the potential for local control of microstructure at large scale• Game-changer: Desired microstructure, PMI, self-healing andradiation resistant properties, can be tailored designed into complex
geometries and hierarchical structures addressing surface/bulk in asingle graded system– Risk: The extent of MBD approaches are intrinsically dependent
on advances in advanced manufacturing and AM• Adoption of advances in manufacturing (e.g. AM, others) in sectors
outside fusion would require appropriate adaptation of process
design to fusion-relevant concepts
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areas may exceed the replenishment c
surface layer, but stagnant lithium conta
high heating rates by vaporization as wehigh surface area 3-D tungsten foam ligam

Emergent fusion materials• Adaptive and self-healing materials,
complex hierarchical composites, complex
alloys, and hybrid liquid/solid systems
Design variables available f
Conceptual drawings of solid tungsten foam/liquid lithium protected
divertor (not to scale);a nominallythick layerof lithium will
Ghoniemand 1-mm
Williams,
2017
flow across a 3-5 mm thick open-cell tungsten foam (diffusion bonded
to the divertor surface) that is filled with stagnant liquid lithium.

– Promise: Complex composites andoptimization
complex alloys may provide
designof geometry• Porous
surfaceradiation-resistant and radiation-tolerant
and typematerials with tailor-designed defect sinkinterfaces, from the PMI
to bulk regions• Substratematerial selection(e.g.
RAFM+Li)• defect-mediatedself-healing
properties available for100 μm
Designvariables– Risks: Unknown PMI properties
andoptimization• Alternative
coolants
andinterface
with
bulk,
hybridsystemswith• Porous surface coolant
geometrypressures
solid/liquid
phasesandcomposites
haveand typewith newthe highest riskheat fluxes• unknownmaterials
properties,
process• Substratematerial
selection(e.g.development
RAFM+Li)
scale-up
and unknown
safety 100 μm• Divertor
chamberand performance margins
shaping and Flame spray
FESAC
debriefing:injection
TEC panel findings
active• Alternative coolants
andcoolant pressures

Wire E

Flame spray
Rindt, PFMC 2017

Wire EDM texture
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Jaworski, FED 2016

J

Divertors and Complex Heat Transfer Systems• Promise on divertor materials: W-based refractory composites
include continuous fiber W-matrix composites, distributed orsemi-interconnected W particulate composites and others– W foam core and other refractory metal shell/core proposed inconjunction with flowing He cooling; high qexhaust ~ 20 MW/m2• Promise on complex heat transfer systems: AM produces
structures with sub-mm precision in meter-size components,
graded material composition, and complex geometries– Novel combinations can address multiple functions, e.g.
material fracture toughness combined with complex graded
porosity for radiation resistance

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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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Control of the Tritium Fueling Cycle• Because D-T fusion power plants must self-generate their T
fuel, novel concepts for fuel production, extraction, andprocessing show transformative potential– Fuel production: several blanket technologies will enablehigher thermal efficiency, and the efficiency by which
tritium can be generated within the blanket, both of which
will significantly reduce fusion plant operating costs– Fuel extraction: new tritium extraction technologies from liquid
metal breeding blankets promise high extraction efficiencies> 85%, which will maximize plant performance and safety– Fuel processing: a new technology may simultaneously
decouple plasma and tritium plant operation and reduce thesize and inventory of the DEMO tritium plant by ~75%

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Tritium Production – DCLL Blankets• Challenge: To satisfy
multiple conflicting material
compatibility, structural
integrity, and lifetime
requirements while removing
heat, breeding tritium andproviding a first wall
– No blanket concepts havedemonstrated therequirements for fusion
power reactors• ITER Test Blanket Module(TBM) research is one of the“unshared” areas• DCLL: Dual coolant leadlithium leading US candidate

Transformative Potential:– Blanket is an unresolved issue with highpayoff: Blanket is recognized by most as
the most critical integrated component
for providing competitive COE• Potential for high tritium breeding ratio• Highest thermal efficiency ~45% of all
ITER-scale and DEMO-relevant
concepts

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Tritium Production – Cellular Media Blankets• While US favors DCLL, most blankets in
ITER TBM use solid ceramic breeders• Promise of Cellular Ceramics– Thermal conductivity substantially
increased relative to pebble beds
– High temperature sintering eliminated,
and tritium breeding ratio (TBR) andbreeder durability are increased– Replacing a pebble bed with a cellular
breeder is anticipated to reduce blanket
size and system cost, and increase TBR
by as much as 20%– Preliminary neutronics calculations
indicate that for a given TBR, overallblanket thickness may be reduced by
as much as 30- 40% compared withpebble bed configurations
FESAC debriefing: TEC panel findings

Cellular Media: A promise of
precisely-crafted porosity &other attractive properties

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Tritium Extraction – Electrolytic Membranes• Challenge: Recently Li, SnLi are being
proposed for flowing liquid metal (LM)first wall and divertor concepts and foruse in tritium breeding blankets (PbLi)
for the next step US fusion reactor– LM flow of these systems must becontinuously processed to T levels < 10
ppm while preserving high LM
temperatures (700 C)– No tritium extraction technologies exist
for any of these LM systems• New mechanism for Li – T separation
using Li conducting electrolytic
membrane: proof of concept achieved• Another technique: use proton
conducting electrolytic membrane
FESAC debriefing: TEC panel findings

Schematic of SRL’s Lithium
Conducting Electrolytic membrane

Schematic of INL’s Proton
Conducting Electrolytic membrane
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Tritium Extraction (cont.) – Vacuum Permeator• Extraction efficiency from LMs limited
by mass transport of tritium from thebulk of the LM to the surface of theextraction membrane• Vacuum permeator: use a Group 5
metallic membrane to push the T
towards the membrane’s surface- Potential of processing the entire liquid metal flow at operating
temperature with an extraction efficiency > 85%, but doesn’t work
well for liquid lithium– A combination of all three technologies promises to fill thetechnology gap by producing extraction technologies for each of
the LM systems– If used in combination, for example a ceramic electrolytic proton
conducting membrane in a vacuum permeator, an extraction
technology emerges that will work for any LM
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Tritium Processing
RFNC-VNIIEF Prometheus MFP• Challenge: A driver of both the fuelingplant’s tritium inventory and processing rate
is tritium burnup fraction (TBF): ITER and
EU DEMO at ~0.35% to 1.5%
– DEMO Tritium Plant 4x larger than ITER
• Metal Foil Pump decouples TBF fromtritium plant operation• Promise:– Potential to reduce the Tritium Plant D+T throughput by 75%– Steady state operation, unlike the cyclic operation of cryopumps– Does not require cryogenic cooling, large pumping ducts or to beisolated from the VV by large valves during regeneration– Operates at high temperatures, can be located close to theplasma, and does not have the large D+T inventory associatedwith cryopumps
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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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Fast flowing liquid metal plasma-facing components• Fast flowing liquid metal plasma
facing components may prove to be
an attractive alternative to handle
both high steady state and transient
plasma heat flux in a fusion reactor
power plant, which would
revolutionize control of the plasmamaterial interface– Fast flow means > 1m/s
– Slow-flow < 10 cm/s considered inadvanced materials as hybrid systems– Can be conceptually applied to the wall
and/or divertor

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Promises of fast flowing liquid metal plasma-facing
components
Perpendicular Heat Flux Limit• Promise: supplement heat
conduction through the substratewith heat convection via liquid
metal flow
Absorbing Li limit

Ablative Li

Sn CPS

Solid W?
Fast Flow– Very high steady, and transient heat exhaust– Tolerable PFC erosion: self-healing surfaces– No dust generation– Eroded chamber material from the main chamber transported to thedivertor could be removed via liquid flow
– Neutron/dpa tolerance; underlying substrate would still have neutroninduced modifications, though– Substrates below LM are protected from plasma-material interactions– Liquid lithium offers high confinement
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Challenges of fast flowing liquid metal plasma-facing
components• Reliably producing stable LM surfaces and flows• Understanding and controlling the LM chemistry• Acceptable temperature windows for specific integrated
scenarios: choice of substrate/coolant that is able to provide for
LM surface temperature control• Fuel retention, recycling and removal in candidate liquid metals• Corrosion issues involving large quantities of LM interfacing with
substrate/bulk components at high temperatures• Wetting vs dry-out effects asymmetric over substrate materials• Neutron damage of solid-based substrate materials• Understanding application of LM to a divertor vs. the first wall
• Plasma confinement with liquid metal PFCs at reactor scale

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Outline• Introduction and process• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Foundational and Enabling Activities
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Foundational and Enabling Activities• In addition to the identified TECs, a number of activities
were identified as foundational on the path toward a fusion
reactor, but not transformative• That is, these capabilities are necessary, and thedevelopment of a fusion power plant probably cannot
happen if we do not continue to develop them
• Also, we identified needed testing facilities to evaluate
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Foundational and Enabling Activities• Novel measurements– Need for radiation hardened diagnostics• Current drive– Injection of EM waves, neutral beams, and helicity• Disruption control and mitigation actuators– Shattered pellets, shell pellets, electromagnetic particle
injector• Exascale computing– Contributes to high fidelity simulations; design optimization
and uncertainty quantification; and operations & control
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Foundational and Enabling Activities (continued)• Advanced divertor concepts– Shape optimization, magnetic variations (“snowflake” and“super-X” and other concepts)• Tritium and lithium safety– Present leading concepts for tritium extraction (molten salt mix+ centrifuge), processing (TCAP), and computational tools(MELCOR)• Advanced power extraction techniques– Supercritical CO2 Brayton cycle with thermal efficiency up to60%• Foundational program areas and test beds
– Need for HTS testing facilities, advanced material testing
facilities, and fuel cycle development facilities
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Summary• Panel identified several promising Transformative Enabling
Capabilities “that could promote efficient advance toward
fusion energy, building on burning plasma science andtechnology.”• First Tier Transformative Enabling Capabilities– Advanced algorithms– High critical-temperature superconductors– Advanced materials– Novel technologies in tritium fuel cycle control• Second Tier Transformative Enabling Capability– Fast flowing liquid metal plasma-facing components• Each of these presents a huge opportunity to accelerate
fusion science & technology toward power production!
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BackupFESAC debriefing: TEC panel findings

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FESAC TEC Community Input Meeting, May 30 – June 1
Technology Assessment “Checklist”
The assessment of each technology application should havethe following components:
1.Description of the technology
2.Application of the technology
3.Critical variable(s) – variable(s) that determines or controls
the output of the technology
4.Design variables – parameters that can be controlled in orderto optimize the critical variable
5.Risks and uncertainties with technology development andperformance
6.Current maturity of the technology
7.Technology development for fusion applications
8.Other considerations / broader impact
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FESAC TEC Community Input Meeting, May 30 – June 1
Technology Readiness Levels•From DOE G 413.3-4A , Technology Readiness Assessment GuideFESAC debriefing: TEC panel findings

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FESAC TEC Community Input Meeting, May 30 – June 1
Technology Readiness Levels
•
•
•
•
•
•
•
•

TRL 1 – pure research
TRL 2 – applied research
TRL 3 – laboratory testing of individual components
TRL 4 – laboratory testing of integrated components
TRL 5 – field testing of integrated components (lab scale)TRL 6 – field testing of scale prototype
TRL 7 – full-scale testing of prototype in cold conditions
TRL 8 – system completed and qualified through test anddemonstration• TRL 9 – Actual system operations in full range of conditions

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FESAC TEC Community Input Meeting, May 30 – June 1
Technology Readiness Levels
TRL Level

Scale of Testing

Fidelity

Environment

Development

9

Full

Identical

Operational (FullRange)

SystemOperations

8

Full

Identical

Operational(Limited Range)

7

Full

Similar

Relevant

6

Engineering / Pilot
Scale

Similar

Relevant

Technology
Demonstration

5

Lab / Bench

Similar

Relevant

4

Lab

PiecesSimulated

Technology
Development

3

Lab

PiecesSimulated

2
1

SystemCommissioning

Paper

Feasibility
Research

Paper

Basic Technology
Research

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Technology Assessment List
1. Technology to be assessed
2. Application of the technology (Note – while the application
presented may be useful for a variety of different machines, it must
be applicable to a tokamak or stellarator concept).
3. Critical variable(s) – variable that determines or controls the outputof the technology• What is the goal for transformative technology – anticipated value or rangeof values for critical variable that needs to be achieved?
• What is the range that is achievable for current state of technology?

4. Design variables – parameters that can be controlled in order to
optimize the critical variable. These could be qualitative.
• Give a description of values that are currently achievable, and a descriptionof what needs to be explored in order to achieve transformation.

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Technology Assessment List
5. Risks and uncertainties• What are the inherent constraints on the technology (such as, limits that are
based on physical laws)? What are the uncertainties in the calculations ofsteps 3 & 4?
• What are the engineering questions and issues (manufacturability, go / no go
issues, etc.). Are there any inherent safety issues?
• Are there institutional, regulatory, or societal obstacles to the development
or use of this technology? Is there resistance to the use of this technology inthe scientific community, or in the relevant industries?

6. Maturity• What progress has been made in this technology in the last 20 years andwhat is the projected development rate?
• What is the technology readiness level for the application?

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Technology Assessment List
7. Technology development for fusion applications• What is required to bring this technology to TRL3 and TRL6? How many
simultaneous innovations are required for this technology to achieve thegoal?
• What is the time horizon for this technology to achieve the goal for theapplication?
• What resources, public and private, are currently available to develop thistechnology? Will developments in this technology from other sources be
useful for the requirements of the application?
• (How) are other nations, through government or private sources, developing
this technology? Are there gaps in global development that represent
possible opportunity for US investment?

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Technology Assessment List
8. Other considerations / broader impact• What is the larger impact that this technology would have on the power plant(to make a particular power plan more attractive, to improve technologies
that it would interface with)?
• What other technologies could serve as an aid to, or a replacement for, thistechnology? What other fields or technologies could be explored that could
meet the requirements of the application?

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Evaluation Metric (1)• Impact (as compared to current conventional technology)– TECE will reduce cost (development cost, construction cost, or
operational cost) of FPP.
– TECE will accelerate schedule to FPP.
– TECE will improve safety, maintainability or public acceptance of
FPP.
– TECE is novel, has high reward / risk ratio.
– TECE will remove major risk to completion of FPP.

• Risks and uncertainties– Engineering questions and issues (manufacturability, go / no-go
issues) are well-defined and understood.
– TECE has no serious safety concerns.
– TECE element has no institutional, regulatory, or societal obstacles to
its development.
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Evaluation Metric (2)• Maturity and development– Current maturity level and development rate of TECE.
– Simultaneous innovations are not required to bring TECE to maturity.
– Cost required to bring TECE to TRL6 is reasonable.
– Time horizon to bring TECE to TRL6 is reasonable.
– Prospect for rapid development from sources outside of fusion– The US has opportunity to take global leadership in this TECE.

• Broader impact– TECE makes the FPP more attractive.
– TECE improves performance of interfacing technologies.

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