ARIES-AT: An Advanced
Tokamak, Advanced Technology
Fusion Power Plant
Farrokh Najmabadi
University of California, San Diego,
La Jolla, CA, United States of America
9th Course on Technology of Fusion Reactors
26 July – 1 August 2004
Erice Italy
Electronic Copy: ARIES Web Site: http://aries.ucsd.edu/PUBLIC
ARIES Research Framework:
Identify Key R&D Issues and
Provide a Vision for Fusion Research
Periodic Input from
Energy Industry
Goals and
Requirements
Scientific & Technical
Achievements
Projections and
Design Options
Evaluation Based on
Customer Attributes
Attractiveness
No: Redesign
Characterization
of Critical Issues
Feasibility
Balanced Assessment of
Attractiveness & Feasibility
Yes
R&D Needs and
Development Plan
ARIES Designs Are Developed Based on a
Reasonable Extrapolation of Physics & Technology
ARIESRules
Rules
ARIES
Plasmaregimes
regimesof
ofoperation
operationare
areoptimized
optimizedbased
basedon
onlatest
latestexperimental
experimental
¾¾ Plasma
achievementsand/or
and/or“well-founded”
“well-founded”theoretical
theoreticalpredictions.
predictions.
achievements
Engineeringsystem
systemisisbased
basedon
on“evolution”
“evolution”of
ofpresent-day
present-daytechnologies,
technologies,i.e.,
i.e.,
¾¾ Engineering
theyshould
shouldbe
beavailable
availableatatleast
leastininsmall
smallsamples
samplesnow.
now. Only
Onlylearning-curve
learning-curve
they
costcredits
creditsare
areassumed
assumedinincosting
costingthe
thesystem
systemcomponents.
components.
cost
Optimizationinvolves
involvestrade-off
trade-offamong
amongPhysics
Physicsand
andEngineering
Engineering
Optimization
constraintsand
andparameters
parameters
constraints
Trade-offbetween
betweenvertical
verticalstability
stabilityand
andplasma
plasmashape
shape(and
(andβ)
β)
¾¾ Trade-off
andfusion
fusioncore
coreconfiguration
configurationand
andblanket
blanketthickness.
thickness.
and
Trade-offbetween
betweenplasma
plasmaedge
edgecondition
conditionand
andplasma
plasmafacing
facing
¾¾ Trade-off
componentscapabilities
capabilities
components
¾¾ ......
Customer Requirements
Top-Level Requirements for Fusion Power Plants
Was Developed in Consultation with US Industry
PublicAcceptance:
Acceptance:
Public
Nopublic
publicevacuation
evacuationplan
planisisrequired:
required: total
totaldose
dose<<11rem
rematatsite
siteboundary;
boundary;
¾¾ No
Generatedwaste
wastecan
canbe
bereturned
returnedtotoenvironment
environmentor
orrecycled
recycledininless
lessthan
thanaafew
few
¾¾ Generated
hundredyears
years(not
(notgeological
geologicaltime-scale);
time-scale);
hundred
Nodisturbance
disturbanceof
ofpublic’s
public’sday-to-day
day-to-dayactivities;
activities;
¾¾ No
Noexposure
exposureof
ofworkers
workerstotoaahigher
higherrisk
riskthan
thanother
otherpower
powerplants;
plants;
¾¾ No
ReliablePower
PowerSource:
Source:
Reliable
Closedtritium
tritiumfuel
fuelcycle
cycleon
onsite;
site;
¾¾ Closed
Abilitytotooperate
operateatatpartial
partialload
loadconditions
conditions(50%
(50%of
offull
fullpower);
power);
¾¾ Ability
Abilitytotomaintain
maintainpower
powercore
core(availability
(availability>>80%);
80%);
¾¾ Ability
Abilitytotooperate
operatereliably
reliablywith
with<<0.1
0.1major
majorunscheduled
unscheduledshut-down
shut-downper
peryear.
year.
¾¾ Ability
EconomicCompetitiveness:
Competitiveness:Above
Aboverequirements
requirementsmust
mustbe
beachieved
achieved
¾¾ Economic
andconsistent
consistentwith
withaacompetitive
competitivelife-cycle
life-cyclecost
costof
ofelectricity.
electricity.
simultaneouslyand
simultaneously
Directions for Optimization
Translation of Requirements to GOALS for
Fusion Power Plants
¾ Have an economically competitive life-cycle cost of electricity:
COE has a “hyperbolic”
• Low recirculating power (Increase plasma Q, …);
dependence (∝ 1/x) and
• High power density (Increase Pf ~ β2BT4 , …)
improvements “saturate”
• High thermal conversion efficiency;
after certain limit
• Less-expensive systems.
¾ Gain Public acceptance by having excellent safety and environmental
characteristics:
• Use low-activation and low toxicity materials and care in design.
¾ Have operational reliability and high availability:
• Ease of maintenance
• Design margins, and extensive R&D.
¾ Acceptable cost of development.
Stay close to present-day
Larger extrapolation from present
Requirements:
There Is Little Economic Benefit for Operating
Beyond ~ 5 MW/m2 of Wall Load (for 1000MWe)
¾ Simple
Simpleanalysis
analysisfor
foraacylindrical
cylindricalplasma
plasma
¾
ARIES-RS
withlength
lengthL:
L:
with
10
Systems code
What we pay for, VFPC
COE (c/kWh)
r
9
∆
8
7
Hyperbolic dependence
6
0
1
2
3
4
5
2
Avg. wall load (MW/m )
Hyperbolic
Wallloading
loadingIIw∝∝1/r
1/r
Wall
dependence
w
setby
byneutron
neutronmfp
mfp
∆∆isisset
2r∆++∆∆22))
FPC==ππLL((2r∆
VVFPC
For rr>>
>>∆∆ , , VVFPC≅≅ 22ππLr∆
Lr∆∝∝11//IIw
For
FPC
w
2
For rr<<
<<∆∆ , , VVFPC≅≅ 22ππLL∆∆2 ≅≅const.
const.
For
FPC
¾ “Knee
“Kneeof
ofthe
thecurve”
curve” isisatatrr≅≅∆∆
¾
Physics&&Engineering
Engineeringconstraints
constraints
¾¾Physics
causedeparture
departurefrom
fromgeometrical
geometrical
cause
dependencee.g.,
e.g.,high
highfield
fieldneeded
needed
dependence
forhigh
highload
loadincreases
increasesTF
TFcost.
cost.
for
ARIES-AToptimizes
optimizesatatlower
lower
¾¾ARIES-AT
wallloading
loadingbecause
becauseofofhigh
high
wall
efficiency.
efficiency.
Continuity of ARIES research has led to the
progressive refinement of research
Improved Physics
ARIES-I (1990):
• Trade-off of β with bootstrap
• High-field magnets to compensate for low β
ARIES-II/IV, 2nd Stability (1992):
• High β only with too much bootstrap
• Marginal reduction in current-drive power
ARIES-RS, reverse shear (1996):
• Improvement in β and current-drive power
• Approaching COE insensitive of power density
ARIES-AT, reverse shear (2000):
• Approaching COE insensitive of current-drive
• High β is used to reduce toroidal field
Need high β equilibria
with high bootstrap
Need high β equilibria
with aligned bootstrap
Better bootstrap alignment
More detailed physics
Evolution of ARIES Designs
1st Stability, High-Field
Nb3Sn Tech.
Option
Reverse Shear
Option
ARIES-I’
ARIES-I
8.0
6.75
5.5
5.2
2% (2.9)
2% (3.0)
5% (4.8)
9.2% (5.4)
Peak field (T)
16
19
16
11.5
Avg. Wall Load (MW/m2)
1.5
2.5
4
3.3
Current-driver power (MW)
237
202
81
36
Recirculating Power Fraction
0.29
0.28
0.17
0.14
Thermal efficiency
0.46
0.49
0.46
0.59
10
8.2
7.5
5
Major radius (m)
β (βΝ)
Cost of Electricity (c/kWh)
ARIES-RS ARIES-AT
Approaching COE insensitive of power density
Approaching COE insensitive of current drive
ARIES-AT
Physics Analysis
ARIES-AT: Physics Highlights
¾ We used the lessons learned in ARIES-ST optimization to reach a
higher performance plasma;
∗ Using > 99% flux surface from free-boundary plasma
equilibria rather than 95% flux surface used in ARIES-RS
leads to larger elongation and triangularity and higher stable β.
¾ ARIES-AT blanket allows vertical stabilizing shell closer to the
plasma, leading to higher elongation and higher β.
¾ Detailed stability analysis indicated that Η−mode pressure &
current profiles and X-point improves ballooning stability.
¾ A kink stability shell (τ = 10 ms), 1 cm of tungsten behind the
blanket, is utilized to keep the power requirements for n = 1
resistive wall mode feedback coil at a modest level.
ARIES-AT: Physics Highlights
¾ We eliminated HHFW current drive and used only lower hybrid
for off-axis current drive.
¾ Self-consistent physics-based transport simulations indicated the
optimized pressure and current profiles can be sustained with a
peaked density profile.
¾ A radiative divertor is utilized to keep the peak heat flux at the
divertor at ~ 5 MW/m2.
¾ Accessible fueling; No ripple losses; 0-D consistent startup; etc.
¾ As a whole, we performed detailed, self-consistent analysis of
plasma MHD, current drive, transport, and divertor (using finite
edge density, finite p′, impurity radiation, etc.)
The ARIES-AT Equilibrium is the Results of
Extensive ideal MHD Stability Analysis
Pressureprofiles
profilesscans
scansshow
showthe
theinterplay
interplay
¾¾Pressure
betweenplasma
plasmaββand
andbootstrap
bootstrapalignment
alignment––
between
optimumprofiles
profilesare
areNOT
NOTatatthe
thehighest
highestβ.β.
optimum
Intermediatennkink
kinksets
setsthe
thewall
walllocation
location
¾¾Intermediate
ARIES-ATplasma
plasmaoperates
operatesatat90%
90%ofof
¾¾ARIES-AT
theoreticalββlimit.
limit.
theoretical
Vertical Stability and Control is a Critical
Physics/Engineering Interface
TSCnonlinear
nonlineardynamic
dynamicsimulations
simulations ofof
¾¾TSC
verticalstability
stabilityand
andfeedback
feedbackcontrol
controlshow
show
vertical
thetradeoff
tradeoffofofpower
powerand
andaccessible
accessibleplasmas
plasmas
the
ARIES-ATelongation
elongationofofκκ==2.2
2.2isis
¾¾ ARIES-AT
consistentwith
withallowed
allowedstabilizer
stabilizerlocation
location
consistent
Major Plasma Parameters of ARIES-AT
Aspect ratio
Major toroidal radius (m)
Plasma minor radius (m)
Plasma elongation (κx)
Plasma triangularity (δx)
Toroidal β ‡
Normalize βΝ ‡
Electron density (1020 m-3)
ITER-89P scaling multiplier
Plasma current
On-axis toroidal field (T)
Current-drive power to plasma (MW)
‡
4.0
5.2
1.3
2.2
0.84
9.2%
5.4
2.3
2.6
13
6
36
ARIES-AT plasma operates at 90% of maximum theoretical limit
ARIES-AT
Engineering Analysis
ARIES-AT Fusion Core
Fusion Core Is Segmented to Minimize
the Rad-Waste
Blanket 1 (replaceable)
Blanket 2 (lifetime)
Shield (lifetime)
Only“blanket-1”
“blanket-1”and
anddivertors
divertors
¾¾ Only
arereplaced
replacedevery
every55years
years
are
ARIES-I Introduced SiC Composites as A HighPerformance Structural Material for Fusion
¾ Excellent safety & environmental
characteristics (very low activation and
very low afterheat).
¾ High performance due to high strength at
o
high temperatures (>1000 C).
¾ Large world-wide program in SiC:
∗ New SiC composite fibers with proper
stoichiometry and small O content.
∗ New manufacturing techniques based
on polymer infiltration results in much
improved performance and cheaper
components.
∗ Recent results show composite
thermal conductivity (under
irradiation) close to 15 W/mK which
was used for ARIES-I.
Improved Blanket Technology
Continuity of ARIES research has led to the
progressive refinement of research
ARIES-I:
• SiC composite with solid breeders
• Advanced Rankine cycle
Starlite & ARIES-RS:
• Li-cooled vanadium
• Insulating coating
ARIES-ST:
• Dual-cooled ferritic steel with SiC inserts
• Advanced Brayton Cycle at ≥ 650 oC
Many issues with solid breeders;
Rankine cycle efficiency
saturated at high temperature
Max. coolant temperature
limited by maximum
structure temperature
High efficiency with Brayton
cycle at high temperature
ARIES-AT:
• LiPb-cooled SiC composite
• Advanced Brayton cycle with η = 59%
Advanced Brayton Cycle Parameters Based on
Present or Near Term Technology Evolved with
Expert Input from General Atomics*
• Min. He Temp. in cycle (heat
sink) = 35°C
• 3-stage compression with 2 intercoolers
• Turbine efficiency = 0.93
• Compressor efficiency = 0.88
• Recuperator effectiveness
(advanced design) = 0.96
• Cycle He fractional ∆P = 0.03
• Intermediate Heat Exchanger
- Effectiveness = 0.9
- (mCp)He/(mCp)Pb-17Li = 1
Keyimprovement
improvementisisthe
thedevelopment
developmentof
ofcheap,
cheap,high-efficiency
high-efficiencyrecuperators.
recuperators.
¾¾ Key
*R. Schleicher, A. R. Raffray, C. P. Wong, "An Assessment of the Brayton Cycle for High Performance Power Plant,"
14th ANS Topical Meeting on Technology of Fusion Energy, October 15-19, 2000, Park City Utah
Recent Advances in Brayton Cycle Leads to
Power Cycles With High Efficiency
T
1
11
2
9'
9
8
He Divertor
Coolant
2'
10
5'
7'
6
Divertor
3
4
S
11
9
Intercooler 1
Intercooler 2
Blanket
LiPb
Blanket
Coolant
10
Recuperator
Intermediate
HX
3
Compressor 1
5
6
7
Compressor 2
1
8
W net
Compressor 3
Turbine
2
4
Heat
Rejection
HX
ARIES-AT: SiC Composite Blankets
¾ Simple, low pressure design with
SiC structure and LiPb coolant
and breeder.
¾ Innovative design leads to high
LiPb outlet temperature
(~1,100oC) while keeping SiC
structure temperature below
1,000oC leading to a high thermal
efficiency of ~ 60%.
¾ Simple manufacturing technique.
¾ Very low afterheat.
¾ Class C waste by a wide margin.
¾ LiPb-cooled SiC composite
divertor is capable of 5 MW/m2
of heat load.
Outboard blanket & first wall
Develop Plausible Fabrication Procedure and
Minimize Joints in High Irradiation Region
1. Manufacture separate halves of the
SiCf/SiC poloidal module by SiCf weaving
and SiC Chemical Vapor Infiltration
(CVI) or polymer process;
2. Manufacture curved section of inner shell
in one piece by SiCf weaving and SiC
Chemical Vapor Infiltration (CVI) or
polymer process;
1
2
3
4
5
3. Slide each outer shell half over the freefloating inner shell;
4. Braze the two half outer shells together at
the midplane;
5. Insert short straight sections of inner shell
at each end;
Brazing
procedure
selected for
reliable
joint contact
area
Butt joint
Mortise and tenon joint
Lap joint
Tapered butt joint
Double lap joint
Tapered lap joint
Multi-Dimensional Neutronics Analysis to
Calculate Tritium Breeding Ratio
and Heat Generation Profiles
•
Latest data and code
•
3-D tritium breeding > 1.1 to
account for uncertainties
•
Blanket configuration and zone
thicknesses adjusted
accordingly
•
Blanket volumetric heat
generation profiles used for
thermal-hydraulic analyses
Innovative Design Results in a LiPb Outlet Temperature
of 1,100oC While Keeping SiC Temperature Below 1,000oC
•
PbLi Inlet Temp. = 764
°C
0.08
0.02
0
Max. SiC/SiC
Temp. = 996°C°
1200
1100
Max. SiC/PbLi Interf.
Temp. = 994 °C First Wall
1000
Channel
900
1100
Bottom
1000
1
2
Poloidal 3
distance
4
(m)
5
6
Top
vback
1200
800
900
800
0.1
0.08
0.06
0.04
0.02
Radial distance (m)
0
Temperature (°C)
0.1
0.04
0.06
Two-pass PbLi flow,
first pass to cool SiCf/SiC box
second pass to superheat PbLi
Pb-17Li
q''plasma
q''back
Poloidal
q'''LiPb
700
Radial
SiC/SiC
Pb-17Li
PbLi outlet temp = 1100 °C
Inner
Channel
SiC/SiC
First Wall
vFW
Out
SiC/SiC Inner Wall
Details of Thermal Analysis of ARIES-AT
First Wall Channel and Inner Channel
ModelDescription:
Description:
Model
AssumeMHD-flowMHD-flow¾¾Assume
laminarizationeffect
effect
laminarization
Useplasma
plasmaheat
heatflux
fluxpoloidal
poloidal
¾¾Use
profile
profile
Usevolumetric
volumetricheat
heatgeneration
generation
¾¾Use
poloidaland
andradial
radialprofiles
profiles
poloidal
Iteratefor
forconsistent
consistentboundary
boundary
¾¾Iterate
conditionsfor
forheat
heatflux
fluxbetween
between
conditions
Pb-17Liinner
innerchannel
channelzone
zoneand
and
Pb-17Li
firstwall
wallzone
zone
first
Calibrationwith
withANSYS
ANSYS2-D
2-D
¾¾Calibration
results
results
Parameters
Parameters
PbLiInlet
InletTemperature
Temperature==764
764°C
°C
¾¾PbLi
PbLiOutlet
OutletTemperature
Temperature==1,100
1,100°C
°C
¾¾PbLi
Radialbuild
build(from
(fromplasma
plasmaside:)
side:)
Radial
CVDSiC
SiCThickness
Thickness==11mm
mm
¾¾CVD
/SiCThickness
Thickness==44mm
mm
SiC/SiC
¾¾SiC
ff
/SiCkk==20
20W/m-K)
W/m-K)
(SiC/SiC
(SiC
ff
PbLiChannel
ChannelThick.
Thick.==44mm
mm
¾¾PbLi
SiC/SiCSeparator
SeparatorThickness
Thickness==55mm
mm
¾¾SiC/SiC
/SiCkk==66W/m-K)
W/m-K)
(SiC/SiC
(SiC
ff
PbLivelocity
velocityininFW
FWChannel=
Channel=4.2
4.2m/s
m/s
¾¾PbLi
PbLivelocity
velocityinininner
innerChannel
Channel==0.1
0.1 m/s
m/s
¾¾PbLi
ARIES-AT Outboard Blanket Parameters
NumberofofSegments
Segments
Number
NumberofofModules
Modulesper
perSegment
Segment
Number
ModulePoloidal
PoloidalDimension
Dimension
Module
Average Module
ModuleToroidal
ToroidalDimension
Dimension
Average
FirstWall
WallSiC
SiC/SiC
/SiCThickness
Thickness
First
ff
FirstWall
WallCVD
CVDSiC
SiCThickness
Thickness
First
FirstWall
WallAnnular
AnnularChannel
ChannelThickness
Thickness
First
AveragePb-17Li
Pb-17LiVelocity
VelocityininFirst
FirstWall
Wall
Average
FirstWall
WallChannel
ChannelRe
Re
First
FirstWall
WallChannel
ChannelTransverse
TransverseHa
Ha
First
MHDTurbulent
TurbulentTransition
TransitionRe
Re
MHD
FirstWall
WallMHD
MHDPressure
PressureDrop
Drop
First
MaximumSiC
SiC/SiC
/SiCTemperature
Temperature
Maximum
ff
MaximumCVD
CVDSiC
SiCTemperature
Temperature
Maximum
MaximumPb-17Li/SiC
Pb-17Li/SiCInterface
InterfaceTemperature
Temperature
Maximum
AveragePb-17Li
Pb-17LiVelocity
VelocityininInner
InnerChannel
Channel
Average
32
32
66
6.8mm
6.8
0.19mm
0.19
mm
44mm
mm
11mm
mm
44mm
4.2m/s
m/s
4.2
3.9xx10
1055
3.9
4340
4340
2.2xx10
1066
2.2
0.19MPa
MPa
0.19
996°C
996°C
1,009°C
°C
1,009
994°C
994°C
0.11m/s
m/s
0.11
Multi-Dimensional Neutronics Analysis was Performed
to Calculate TBR, activities, & Heat Generation Profiles
Verylow
lowactivation
activationand
andafterheat
afterheat
¾¾ Very
Leadtotoexcellent
excellentsafety
safetyand
and
Lead
environmentalcharacteristics.
characteristics.
environmental
Allcomponents
componentsqualify
qualifyfor
forClassClass¾¾ All
disposalunder
underNRC
NRCand
andFetter
Fetter
CCdisposal
Limits. 90%
90%ofofcomponents
components
Limits.
qualifyfor
forClass-A
Class-Awaste.
waste.
qualify
On-lineremoval
removalofofPo
Poand
andHg
Hg
¾¾ On-line
fromLiPb
LiPbcoolant
coolantgreatly
greatly
from
improvesthe
thesafety
safetyaspect
aspectofofthe
the
improves
systemand
andisisrelatively
relativelystraight
straight
system
forward.
forward.
Major Engineering Parameters of ARIES-AT
Fusionpower
power(MW)
(MW)
Fusion
EnergyMultiplication,
Multiplication,M
M
Energy
ThermalPower
Power(MW)
(MW)
Thermal
Peak/Avg.first
firstwall
wallheat
heatflux
flux(MW/m
(MW/m22))
Peak/Avg.
Peak/Avg.neutron
neutronwall
wallload
load(MW/m
(MW/m22))
Peak/Avg.
LiPbcoolant
coolantoutlet
outlettemperature
temperature(°C)
(°C)
LiPb
Thermalefficiency
efficiency
Thermal
Grosselectric
electricpower
power(MW)
(MW)
Gross
Recirculatingpower
powerfraction
fraction
Recirculating
Costof
ofelectricity
electricity(c/kWh)
(c/kWh)
Cost
1,755
1,755
1.1
1.1
1,897
1,897
0.34/0.26
0.34/0.26
4.9/3.3
4.9/3.3
1,100
1,100
0.59
0.59
1,136
1,136
0.14
0.14
55
ARIES-AT Toroidal-Field Magnets
On-axistoroidal
toroidalfield:
field: 66TT
¾¾ On-axis
Peakfield
fieldatatTF
TFcoil:
coil: 11.4
11.4TT
¾¾ Peak
Use of High-Temperature Superconductors
Simplifies the Magnet Systems
¾ HTS does not offer significant
superconducting property advantages
over low temperature superconductors
due to the low field and low overall
current density in ARIES-AT
¾ HTS does offer operational advantages:
∗ Higher temperature operation (even
77K), or dry magnets
∗ Wide tapes deposited directly on
the structure (less chance of energy
dissipating events)
∗ Reduced magnet protection
concerns
¾ and potential significant cost advantages
Because of ease of fabrication using
advanced manufacturing techniques
YBCO Superconductor Strip
Packs (20 layers each)
CeO2 + YSZ insulating coating
(on slot & between YBCO layers)
8.5
430 mm
Inconel strip
ARIES-AT Uses a Full-sector Maintenance
Scheme and a High Availability Is Predicted
Power Core Removal Sequence
Caskcontains
containsdebris
debrisand
anddust
dust
¾¾Cask
Vacuumvessel
vesseldoor
doorremoved
removed
¾¾Vacuum
andtransported
transportedtotohot
hotcell
cell
and
Coresector
sectorreplaced
replacedwith
with
¾¾Core
refurbishedsector
sectorfrom
fromhot
hotcell
cell
refurbished
Vacuumvessel
vesseldoor
doorreinstalled
reinstalled
¾¾Vacuum
Multiplecasks
casksand
andtransporters
transporters
¾¾Multiple
canbe
beused
used
can
Our Vision of Magnetic Fusion Power Systems Has
Improved Dramatically in the Last Decade, and Is Directly
Tied to Advances in Fusion Science & Technology
Major radius (m)
Estimated Cost of Electricity (c/kWh)
10
14
12
10
8
6
4
2
0
9
8
7
6
5
4
3
2
1
0
Mid 80's
Physics
Early 90's
Physics
Late 90's
Physics
Advance
Technology
Present ARIES-AT parameters:
Major radius:
5.2 m
Toroidal β:
9.2%
Wall Loading:
4.75 MW/m2
Mid 80's
Pulsar
Early 90's
ARIES-I
Fusion Power
Net Electric
COE
Late 90's
ARIES-RS
2000
ARIES-AT
1,720 MW
1,000 MW
5 c/kWh
ARIES-AT is Competitive
with Other Future Energy Sources
Estimated range of COE (c/kWh) for 2020*
7
6
5
AT 1000 (1 GWe)
AT 1500 (1.5 GWe)
4
3
2
1
0
Natural Gas
Coal
Nuclear
EPRI Electric Supply Roadmap (1/99):
Business as usual
Impact of $100/ton Carbon Tax.
Wind
Fusion
(Intermittent) (ARIES-AT)
Estimates from
Energy Information Agency
Annual Energy Outlook 1999
(No Carbon tax).
* Data from Snowmass Energy Working Group Summary.
Main Features of ARIES-AT2
(Advanced Technology & Advanced Tokamak)
¾ High Performance Very Low-Activation Blanket: New hightemperature SiC composite/LiPb blanket design capable of
achieving ~60% thermal conversion efficiency with small nucleargrade boundary and excellent safety & waste characterization.
¾ Higher Performance Physics: reversed-shear equilibria have
been developed with up to 50% higher β than ARIES-RS and
reduced current-drive power.
¾ The ARIES-AT study shows that the combination of advanced
tokamak modes and advanced technology leads to attractive
fusion power plant with excellent safety and environmental
characteristics and with a cost of electricity which is competitive
with those projected for other sources of energy.