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Fusion Fire Powers the Sun

Can we make Fusion Fire on earth?

2AES, ANL, Boeing, Columbia U., CTD, GA, GIT, LLNL, INEEL, MIT, ORNL, PPPL, SNL, SRS, UCLA, UCSD, UIIC, UWisc

FIRE Collaboration http://fire.pppl.gov

Creating and Controlling a Fusion Fire

in the Laboratory

Dale MeadePrinceton, Plasma Physics Laboratory

Division of Plasma Physical SocietyKorean Physical Society

Jeju, KoreaOctober 23, 2004

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Topics to be Discussed

• Need for Fusion

• Vision for Magnetic Fusion Power Plant

• Requirements and Critical Issues for Magnetic Fusion

• Recent Progress

• Requirements for a Fusion Fire Test

• Status of Plans for Building a Fusion Fire

• Concluding Remarks

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The Case for New Sources of Energy

• Increasing evidence that release of greenhouse gases is causing global climate change

• World population increases and demand for economic development require a large increase in worldwide energy production– Most population growth is in urban areas

• Implies need for large, centralized power generation

– Worldwide oil and gas production is near peak or past

• Secure energy supply with low cost and wide availability is needed for all countries

• A portfolio of alternative energy sources is required including fusion.

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Fusion Reactions

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10 - 20 keVIs optimum

~ (plasma pressure)2 Need 10 atmospheres @ 10 keV

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Toroidal Magnetic Confinement

Charged particles have helical orbits in a magnetic field; they describe circular orbits perpendicular to the field with gyro-radius rl=v/Ω, where Ω=qB/mc

“TOKAMAK”

(Russian abbreviation for “toroidal chamber” with magnetic fields); includes an induced toroidal plasma current to form, heat and confine the plasma

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What is Inside a Tokamak?

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High Power DensityPf/V~ 6 MW-3

~10 atmn ≈ 4 MWm-2

High GainQ ~ 25 - 50

nET ~ 6x1021 m-3skeVP/Pheat = f ≈ 90%

Steady-State~ 90% Bootstrap

ARIES Economic Studies have Defined the Plasma Requirements for an Attractive Fusion Power Plant

Plasma ExhaustPheat/Rx ~ 100MW/m

Helium PumpingTritium Retention

Plasma ControlFueling

Current DriveRWM Stabilization

Significant advances are needed in each area. High gain, high power density and steady-state are the critical issues.

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Critical Issue #1- High Fusion Gain (confinement): FIRE and ITER Require Modest (2.5 to 4.5) Extrapolation

• Tokamaks have established a solid basis for confinement scaling of the diverted H-Mode.

• BE is the dimensionless metric for confinement time projection

• nET is the dimensional metric for fusion - nET = B2E = B . BE

• ARIES-RS Power Plants require BE only slightly larger than FIRE due high and B.

ARIES-RS (Q = 25)

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Present Data

Region

CREST

ARIES-AT

ARIES-RSASSTR

SSTR

Steady StateReactor

Designs

Bt(T)2 4 6 8 10 11

6

5

4

3

2

1

00

N

• ARIES and SSTR/CREST studies have determined requirements for an attractive power plant.

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ITER

AT

H

• ITER would expand region toN ≈ 3 and fbs ≈ 50% at moderate magnetic field.

FIRE

AT

H

• FIRE would expand region to N≈ 4 and fbs ≈ 80% at reactor-like magnetic field.

Attractive Reactor Regime Needs Highish and B

Modification of JT60-SC Figure

• Existing experiments, KSTAR, EAST and JT-SC would exp-

and high N region at low field.

EASTJT60-SC

KSTAR

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Economic Reactors Will Require Efficient Magnetic Utilization⟨p⟩

( )atm

0.1110301101001000TPXIGNITOR-ARIES AT2ASSTRH2 O Cu Coil ST Ops MaxBcoil2(T2)ProjectedAchieved1%fusion=2%LN2 Cu Coil, Bitter WedgedOps Max-ARIES ST0.5%NSTX-FIRE AT-ARIES RS-FIRE H- & -ITER H ITER ATTFTR-C Mod- C Mod AT- ( )Alc C OHJET -PBX M•“ ” , Attractive fusion systems require both high field high and efficient utilization.

• Advanced tokamaks offer the best combination of high .and achievable high field

NSTX≈5MWm-3≈0.5MWm-3Nb SnCIC

3 CSCoil

Ops Maxfusion=⟨p⟩/Bcoil260JT U -DIII D Critical Issue #2 - High Power Densities: Requires

Significant (x10) Extrapolation in Plasma Pressure

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Steps to a Fusion Demo

Today’s Tokamaks

Advanced TokamaksLong Pulse

Burning PlasmaTokamaks

Fusion Demo

Fusion Fire

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KSTAR TokamakTaejon, S. KOREA

New Generation Advanced Tokamak

• Latest physics ideas in design and systems to control plasma

• Long pulses up to 300s

• Superconducting coils but without a burning plasma

• Comparable in size to largest experiments of today

• first plasma tests in late 2006

R = 1.8 m, B= 3.5 T, Ip = 2 MA,

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Two Furnaces for Testing a Fusion Fire

ITER (International Thermonuclear Experimental Reactor)• Discussions started in 1985• Demonstrate scientific and technical feasibility of fusion• Six party international partnership (JA,EU,RF,US,CN,ROK)• To be built in Japan or France (Cost ~ $5B)• Under negotiation ( decision expected by December 2004)

FIRE (Fusion Ignition Research Experiment)• Lowest cost approach for creating and controlling fusion fire• International Collaboration lead by the US• To be built in the US (Cost ~ $1B)• Under design as back up, put forward if no ITER decision

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The Fusion Fire Step to a Fusion Power Plant

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FESAC Recommended a Robust Strategyfor Burning Plasmas (Sep. 2002)

Based on the community consensus at Snowmass, FESAC found that:

“ITER and FIRE are each attractive options for the study of burning plasma science.Each could serve as the primary burning plasma facility, although they lead todifferent fusion energy development paths.

Because additional steps are needed for the approval of construction of ITER orFIRE, a strategy that allows for the possibility of either burning plasma option isappropriate.”

FESAC recommended a robust strategy:1. that the US should seek to join ITER negotiations as a full participant

- US should do analysis of cost to join ITER and ITER project cost.- negotiations and construction decision are to be concluded by July 2004.

2. that the FIRE activities continue toward a Physics Validation as plannedand be prepared to start Conceptual Design at the time of the ITER Decision.

3. If ITER does not move forward, then FIRE should be advanced as aU.S.-based burning plasma experiment.

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Fusion Development Considerations for FIRE

• Address key physics issues for an advanced reactor • burning plasma scenarios similar to ARIES • controlled burn of high power density plasma with Q >5, fBS ≈ 80%

• Focus technology on areas coupled to the plasma• high power density plasmas • plasma facing components• plasma control technologies

• Limit scope/size/cost of the device• size comparable to today’s largest tokamaks to reduce cost • only integrate items that are strongly coupled: plasma-PFCs

These are some of the biggest challenges for fusion, success in these areas would lead to an attractive

Demo.

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Advanced Toroidal Physics (100% Non-inductively Driven AT-Mode)Q ~ 5 as target, higher Q not precludedfbs = Ibs/Ip ~ 80% as target, ARIES-RS/AT≈90%

N ~ 4.0, n = 1 wall stabilized, RWM feedback

Quasi-Stationary Burn Duration (use plasma time scales)Pressure profile evolution and burn control ~ 20 to 40 E

Alpha ash accumulation/pumping ~ 4 to 8 He

Plasma current profile redistribution ~ 2 to 5 CR

Divertor pumping and heat removal ~ 15 to 30 divertor

First wall heat removal > 1 first-wall

FIRE Physics Objectives

Burning Plasma Physics (Conventional Inductively Driven H-Mode)Q ~10 as target, higher Q not precludedf = P/Pheat ~ 66% as target, up to 83% @ Q = 25

TAE/EPM stable at nominal point, access to unstable

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Fusion Ignition Research Experiment (FIRE)

• R = 2.14 m, a = 0.595 m

• B = 10 T, (~ 6.5 T, AT)

• Ip = 7.7 MA, (~ 5 MA, AT)

• PICRF = 20 MW

• PLHCD ≤ 30 MW (Upgrade)

• Pfusion ~ 150 MW

• Q ≈ 10, (5 - 10, AT)

• Burn time ≈ 20s (2 CR - Hmode)

≈ 40s (< 5 CR - AT)

• Tokamak Cost = $350M (FY02)

• Total Project Cost = $1.2B (FY02)

1,400 tonneLN cooled coils

Mission: to attain, explore, understand and optimize magnetically-confined fusion-dominated plasmas

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FIRE is Based on ARIES-RS Vision

• 40% scale model of ARIES-RS plasma

• ARIES-like all metal PFCs

• Actively cooled W divertor

• Be tile FW, cooled between shots

• Close fitting conducting structure

• ARIES-level toroidal field

• LN cooled BeCu/OFHC TF

• ARIES-like current drive technology

• FWCD and LHCD (no NBI/ECCD)

• No momentum input

• Site needs comparable to previous

DT tokamaks (TFTR/JET).

• T required/pulse ~ TFTR ≤ 0.3g-T

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No He Pumping

• Needs He pumping technology

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“Steady-State” High- Advanced Tokamak Discharge on FIRE

0 1 2 3 4

time,(current redistributions)

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FIRE AT Mode Pulse Length is not Limited by Cu Coils

Q = 5Nominal operating point

• Q = 5• Pf = 150 MW, • Pf/Vp = 5.5 MWm-3 (ARIES)• ≈ steady-state 4 to 5 CR

Physics basis improving (ITPA)• required confinement H factor

and N attained transiently• C-Mod LHCD experiments will be very important

First Wall is the main limit not TF• Improve cooling• revisit FW design

Opportunity for additional improvement.

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ITER and FIRE Advanced Tokamak Operating Modes Pose Challenges for Plasma Technology

Technology ItemsExisting

ToksITER-AT FIRE-AT ARIES-

RS/AT

B(T) 1.5 - 7 5.3 6.5 6 - 8

Ip(MA) 1 - 3 9 5 11

Fusion Power Density (MWm-3)

0.15 - 0.3 0.5 5 5 - 6

FW -N (MW/m-2) 0.1 0.5 2 4

FW - Prad (MWm-2) 5 15 15 100

First Wall C, Be Be Be Mo

Div Target (MWm-2) 1 5 - 20 5 - 20 5 - 20

Divertor Target C, (Mo,W) C,W? W W

Pulse Length(s, cr)Typical 5, 2

(max = 5 hrs)3000, 8 40, 5 months

Cooling Divertor, First Wall

Inertial(SS)

inertial

Steady

steady

Steady

inertial

Steady

steady

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Status and Plans for FIRE

• FIRE has made significant progress in increasing physics and engineering capability since the Snowmass/FESAC recommendations of 2002.

• FIRE successfully passed the DOE Physics Validation Review (PVR) in March 2004.“The FIRE team is on track for completing the pre-conceptual design within FY 04. They will then be ready to launch the conceptual design. The product of their work, and their contributions to and leadership within the overall burning plasma effort, is

stellar. ” - PVR Panel

• Most of the FIRE resources were transferred to US - ITER activities in late 2003. The resources remaining in 2005 will focus on development of advanced capabilities for ITER - e.g., integrated AT modes, high power PFCs.

• The present US plan assumes that a decision to construct ITER is imminent. If an agreement on ITER is not attained, FIRE is ready, to be put forward as recommended by FESAC.

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ITER has been designed, now ready to build

Toroidal Field CoilNb3Sn, 18 coils

Poloidal Field CoilNb-Ti, 6 coils

Central SolenoidNb3Sn, 6 modules

Blanket Module421 modules

Vacuum Vessel9 sectors

Cryostat24 m high x 28 m dia.

Port Plug6 heating3 test blankets2 limitersrem. diagnostics

Divertor54 cassettes

Sharing of construction costs has been agreed

• CN: magnet supports,feeders, correction coils, conductors, blanket (0.2), cryostat, gas injection, casks (0.5), HV substation, AC/DC (0.35), diag.

• EU: TF(0.5), conductors, cassette and outer target, vac.pumps, div. RH, casks (0.5), isotope sep., IC, EC, diag.

• JA: TF(0.5), conductors, inner target, blanket RH, EC, diag.

• KO: conductors, vessel ports (0.67), blanket (0.2), assembly tools, thermal shield, T storage, AC/DC (0.65), diag.

• RF: PF1, conductors, vessel ports (0.33), blanket (0.2), port limiters, flexibles, dome and PFC tests, Discharge circuits, EC, diag.

• US: CS(0.5), conductors, blanket (0.1), vac.pumps, pellet inj., vessel/in-vessel cooling, tok exh. proc., IC, EC, diag.

Party Share Total

CN-KO-RF-US 10% each 40%

JA + EU

Host:

36%+A

Non-Host: 10%+B

(A+B=14%)

60%

• Host provides Buildings and Utilities. Remaining allocation (A+B) depends on site and final agreement.

• Fund (10%): Feeders, Shielding, viewing, NB RH, Hot cell eq., cryo dist., CODAC, installation and test, other sundry items

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ITER site needs to be decidedCadarache (France) or Rokkasho (Japan)?

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Concluding Remarks

Magnetic Fusion has made remarkable progress during the past decade and has achieved:

• fusion fuel temperatures of 500 million degrees C• fusion power production of 16 million watts• fuel density x confinement ≈ 50% of that needed for ignition • better understanding of plasma confinement and stability

More important than ever to find out if fusion can be an energy source for the world.

Magnetic Fusion is now ready to take the crucial step of:• building and testing a fusion fire in the laboratory• two attractive options (ITER and FIRE) are available• a decision on ITER is expected within months• if a decision can not be reached on ITER, FIRE could be built to

create, control and optimize a fusion fire in the laboratory.

Thanks for your interest. More info at http://fire.pppl.gov

We will also need fusion at night..

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