ITERThe past, present and future

1985 to 2007

Garry McCracken

What is ITER?• ITER is a design for a nuclear fusion experiment to demonstrate the feasibility of a fusion power plant. • First proposed as a collaboration between the

US and the Soviet Union by Ronald Reagan and Mikhail Gorbachev at a Summit meeting Geneva 1985

• The experiment is jointly funded by China, Europe, India, Japan, Korea, Russia and the US

representing more than half the population of the world

What is Nuclear Fusion?• Nuclear fusion is the reaction between two nuclei to form

a larger one. When the mass of the product nucleus is less than the mass of the two original nuclei the excess mass is released as energy

»

+ 4 MeV

+ 3.3 MeV

+ 17.6 MeV Key reaction

+ 18.3 MeV

Nuclear Fusion Power Plants

• Assuming that the problem of plasma confinement would be solved the design of fusion power plants was considered very early in the international fusion program

• A patent for a fusion power plant was filed in 1946 by GP Thomson and M Blackman of Imperial college London.

• In the 1950’s Lyman Spitzer at Princeton NJ considered the design of a fusion reactor

• In the late 1960’s after the success of the Soviet tokamaks there were many attempts to design tokamak reactors, particularly in the US and the UK

Conceptual fusion reactor

Deuterium

Lithium blanketTritium

D+T plasma

Steam Generator

Turbine Generator

Lithium

Primary Fuels

Vacuum

Deuterium Tritium

Reprocessing of gases

Heat exchanger

Fusion Reactor

Electricity grid

Helium + hydrogen waste gases

Exhaust Gases -- Deuterium, tritium hydrogen , helium

Attempts to produce fusion power on earth

• Fusion reaction occur in the sun because gravity holds the reacting particles close enough together for the reaction to occur

• On earth man first succeeded in producing the reaction in the hydrogen bomb in 1952 This destructive approach is of no use for generating useful power

• Instead we have tried to produce the reaction in a controlled manner by using magnetic and electric fields. Experiments started in the late 1940’s and have continued to the present day.

• Early successes were the Soviet tokamaks (1960’s)• The first demonstration of controlled DT fusion reactions was

in 1991 on the European tokamak JET. About 1 MW was produced for aver 1 second

Tokamak PrinciplesConfinement is produced by the combination of toroidal field produced by external coils and a poloidal field produced by a current in the plasma

Experimental fusion power production

JET and TFTR have demonstrated fusion reactions.

The maximum power achieved was 16 MW

The value of

Q=Power out/power in =0.6

Q in ITER is planned to be 10

The INTOR programme

• INTOR was the first international attempt to design a fusion reactor

• In the late 1970’s 3 large tokamaks were being designed JET, TFTR and JT60

• IAEA proposed a workshop in Vienna with US, USSR, JA and EU

• This defined a reactor design with S/C magnets, T breeding, remote handling and materials testing, 1980

• DESIGN had R=5m, a=1.2m Ip=8-10 MA

Scaling confinement time from experiments to ITER

Origins of ITER

• Velikhov, Gorbachev and Mitterand

• Regan -Gorbachev summit, Geneva Nov 1985

• Japan and Europe invited to join a 4 party programme to build a reactor

• IAEA invitation to Vienna workshop March 1987. Report produced and Joint Working site at Garching(Germany) agreed

President Reagan, GorbachevGeneva Summit, 1985

Designing ITER

• Conceptual design 1988-90

• Engineering design 1992-94 (Rebut)

• Engineering design 1994-98 (Aymar)

• Redesign 1998-2001 (Aymar)

Problems over siting design team

• 3 sites proposed

• Japan Naka (External components)• Europe Garching, Germany (Internal comp.)• USA San Diego (Integration)

Three joint sites agreed. This led to a complicated structure and a lot of travelling

Engineering Design 1992-94

Director Paul-Henri Rebut (centre)Deputy directors(from left) Valery Chuyanov (RF), Michel Huguet (EU) Ron Parker (US), Yasuo Shimomura (JA)

Robert AymarDirector (1994-2003)

Comparison of JET and ITER

JETR=3mIp=4MA

ITERR=6.2mIp=15MA

JET is the largest presently existing tokamak

The 2001 ITER design

Toroidal Field CoilNb3Sn, 18, wedged

Central SolenoidNb3Sn, 6 modules

Poloidal Field CoilNb-Ti, 6

Vacuum Vessel9 sectors

Port Plug heating/current drive, test blanketslimiters/RHdiagnostics

Cryostat24 m high x 28 m dia.

Major plasma radius 6.2 m

Plasma Volume: 840 m3

Plasma Current: 15 MA

Typical Density: 1020 m-3

Typical Temperature: 20 keV

Fusion Power: 500 MWMachine mass: 23350 t (cryostat + VV + magnets)- shielding, divertor and manifolds: 7945 t + 1060 port plugs- magnet systems: 10150 t; cryostat:  820 t

Seven Large Projects to study manufacturing

• Central solenoid coil (Nb/Sn S/C) L1

• Toroidal field coil (Nb/Sn S/C) L2

• Sector of the vacuum vessel L3

• Blanket module L4

• Divertor cassette L5

• Blanket remote handling system L6

• Divertor remote handling system L7

Magnets and StructuresSuperconducting. 4 main subsystems:•18 toroidal field (TF) coils produce confining/stabilizing toroidal field;

•6 poloidal field (PF) coils position and shape plasma;

•a central solenoid (CS) coil induces current in the plasma.

•correction coils (CC) correct error fields due to manufacturing/assembly imperfections, and stabilize the plasma against resistive wall modes.

Vessel, Blanket and divertorThe double-walled vacuum vessel is lined by modular removable components, including blanket modules, divertor cassettes, and diagnostics sensors, as well as port plugs for limiters, heating antennae, diagnostics and test blanket modules. All these removable components are mechanically attached to the VV. The total vessel/in-vessel mass is ~10,000 t.

These components absorb most of the radiated heat from the plasma and protect the magnet coils from excessive nuclear radiation. The shielding is steel and water, the latter removing heat from absorbed neutrons. A tight fitting configuration of the VV to the plasma aids passive plasma vertical stability, and ferromagnetic material “inserts” in the VV located in the shadow of the TF coils reduce toroidal field ripple and its associated particle losses.

Safety and Environmental Characteristics

•ITER will be a precedent for future fusion licensing

•Work towards internationally accepted basic principles

and safety criteria for fusion energy

•Interact with regulatory experts to ensure ITER

options can be licensed in any Party

Parameters of the ITER designs Conceptual ŅFinalÓ Redesign (1990) (1998) (2001)

Plasma major radius (m) 6.0 8.1 6.1Plasma width at mid-plane (m) 2.15 2.8 2.0Elongation (ratio of plasma height to width) 1.98 1.6 1.7Toroidal field on plasma axis (T) 4.85 5.7 5.3Nominal maximum plasma current (MA) 22 21 15Nominal fusion power (MW) 1000 1500 500Pulse length more than (s) 200 1000 400Number of toroidal field coils 16 20 18Neutron wall loading (MW/m2) 1.0 1.0Divertor double single single

The Rebut design in 1994 had 24 field coils but was otherwise similar to the 1998 design

Political aspects• 1998-2001 US withdrawal, no site offered• June 2001, Canadian site proposed• June 2002 JA offers Rokkasho, EU offers Caderache

and Vandellos -- now 4 sites!• EU withdraws Vandellos, CA withdraws• Jan 2003 China joins, US rejoins, KO joins• Washington meeting to decide site ends in stalemate• 2003-2006 Battle between EU and JA for site

Proposal for a broader approachAgreement on the Caderache site

Signing the treaty, Paris, 21 November 2006

The ITER buildings today

Cadarache, near Aix-en-Provence, France

ITER collaboration•For its size and cost and the involvement of virtually all the most developed countries, •representing over half of today world’s population ITER will become a new reference• term for big science projects.

•The ITER project is one of the world’s biggest scientific collaboration.

The ITER organization

ITER Director-General

Dr Kaname Ikeda (Japan)

Deputy Director General and Project construction leader

Dr Norbert Holtkamp EU

Deputy Director Generals

Valery Chuyanov RF Fusion Science

Gary Johnson USTokamak

Carlos Alhedre EUSafety, Environment

Dhijaj Bora (IN) ControlDiagnostics and Heating

Kim KO, Engineering,Fuel cycle

Wang CN Administration,Finance

Proposed ITER Site Layout

Staff Planning

Staff Ramp Up IO Team

0

100

200

300

400

500

600

700

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015

Calendar Year

Nu

mb

er

Sum PPY: 1800

Sum Support: 2760

Sum Total

Indicative Construction Schedule

Indicative Operation Schedule

2nd yr 4th yr 5th yr 8th yr3rd yr 10th yr7th yr 9th yr6th yr1st yrConstruction Phase

Mile StoneFirst Plasma Full Non-inductive

Current DriveFull Field, Current& H/CD Power

Q = 10,500 MW,400 s

Short DTBurn

Q = 10,500 MW

Installation &Commissioning

For activation phase

For high duty operation

BasicInstallation

Upgrade

- Commissioning- Achieve good vacuum & wall condition

Operation

EquivalentNumber ofBurn Pulses(500 MW x 440s*)

Fluence**

Low Duty DT

- Development of full DT high Q- Developmentt of non-inductive operation aimed Q = 5- Start blanket test

1 2500 3000300015001000750

- Commissioning w/neutron- Reference w/D- Short DT burn - Improvement of inductive and

non-inducvtive operation- Demonstration of high duty operation- Blanket test

- Machine commissioning with plasma- Heating & CD Expt.- Reference scenarios with H

High Duty DT

0.006MWa/m2

0.09MWa/m2

First DT Plasma Phase H Plasma Phase D Phase

Blanket Test

- Electro-magnetic test- Hydraulic test- Effect of ferritic steel etc.

- Short-time test of T breeding- Thormomecanics test- Preliminary high grade heat generation test, etc.

- Neutronics test- Validate breeding performance

- On-line tritium recovery- High grade heat generation- Possible electricity generation, etc.

Performance TestSystem Checkout and Charactrerization

* The burn time of 440 s includes 400 s flat top and equivalent time which additional flux is counted during ramp-up and ramp-down.** Average Fluence at First Wall (Neutron wall load is 0.56 MW/m2 in average and 0.77MW/m2 at outboard midplane.)

Why is ITER important?

Features•Virtually inexhaustible power•No CO2 emissions •High energy density fuel

–1 gram D-T = 26000 kW·hr of electricity (~10 Tonnes of Coal !!)

•Inherently Safe Controllability–low fuel inventory, ease of burn termination, self-limiting power level–No chain reaction to control–low power and energy densities, large heat transfer surfaces and heat sinks

Issues•Fusion reaction is difficult to start and maintain

–High temperatures (Millions of degrees) required–Technically complex & LARGE devices are required

The Broader Approach

• During the JA-EU discussions over ITER site a “Broader Approach” was suggested.

• This now has 3 parts– International Fusion Irradiation Facility (IFMIF)– International Fusion Research Centre– Advanced S/C tokamak at Naka Japan

The research centre will work on DEMO

Provisional future programmeyear 0

2005 2010 2015 2020 2025 2030 2035 2040 2045 2050

5 10 15 20 4525 30 35 40

operation: priority materials

conceptual design

construction

construction

upgrade,construct

operateTodays

expts.

licensing

H & D operation

low-duty D-T operation

high-duty D-T operation

TBM: checkout and characterisation

TBM performance tests & post-exposure tests

second D-T operation phaseITER

EVEDA (design)

other materials testingIFMIF

engineering designconstruction phase 1

blanket construction

phase 2blanket

construction &installation

operation phase 1operation phase 2

blanket design

phase 2 blanket design

licensing

DEMO(s)

engineering designconstruction operateconceptual design

licensing

Commercial Power plants

blanket optimisation

plasma performance confirmation

materials characterisation

design confirmation

technology issues (e.g. plasma-surface interactions)

plasma issues

single beam

licensing licensing

plasma confirmation

materials optimisation

plasma optimisation

mobilis-ation

Project Schedule (2006)

2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015

ITER IOLICENSE TO CONSTRUCT

TOKAMAK ASSEMBLY STARTS

BidContract

EXCAVATETOKAMAK BUILDING

OTHER BUILDINGS

TOKAMAK ASSEMBLY

COMMISSIONING

MAGNET

VESSEL

Bid Vendor’s Design

Bid

Installcryostat

First sector Complete VVComplete blanket/divertor

PFC Install CS

First sector Last sector

Last CSLast TFCCSPFC TFCfabrication start

Contract

Contract

2016

Construction License Process

The ITER site

Tokamak building

Tritium building

Cryoplant buildings

Magnet power convertors buildings

Cooling towers

TheHot cell

The site will cover about 60 ha, with buildings over 170m long