H. Bolt, 20.04.23

Fast Track Concept in the European Fusion Programme Harald Bolt Max-Planck Institute for Plasma Physics, GarchingEURATOM Association

ContentsIntroductionMandate„Fast Track“: ConclusionsRole of materials R&D for fusion power development

International Symposium for ITER

H. Bolt, 20.04.23

„fast track initiative“: Background

1. British government to EU Commission and Research Ministers (24 Oct. 2001) concerns: stability of supply of fossil energy; global warming, decreasing share of electricity from fission convincing reasons for significant role of fusion:

- demonstrate feasibility of fusion within 20-30 years- accelerate materials R&D for fusion (in parallel with ITER)- bring US „on board“ - including financial participation- involve industry in steering function

2. EU Research Council (31 Oct. 2001)takes up matter

3. Fast Track Working Group (27 Nov. 2001)report to Research Council

4. EU Research Council (10 Dec. 2001)positive response

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Mandate

Mission

Assess scope and ways of organising the programme with a view toproducing a "fast track" roadmap for fusion, with the clear goal ofenergy production within 20-30 years.

Specific tasks

(report before Research Council of 10 December 2001):

1. First assessment of a fast track schedule

2. Acceleration of materials work alongside work on ITER

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Members of the group

Prof. David KING (Chairman), UKProf. Angelo AIRAGHI, ItalyProf. Harald BOLT, GermanyDr. Joaquin CALVO, SpainMr. Bernard FROIS, FranceMr. Marcel GAUBE, BelgiumDr. Lars HÖGBERG, SwedenMr. Gabriel MARBACH, FranceMr. Steven WALSGROVE, UK

H. Bolt, 20.04.23

Next

Tentative Roadmap of Achievements starting from the decision to construct the Next Step

Main Achievements Required

⟨ Production and control of long pulse-burning plasma

⟨ Heat and particles exhaust (plasma facing components)

⟨ Test of breeding blanket modules for DEMO

⟨ Net electricity production (full hot breeding blanket)

⟨ High reliability of operations

⟨ Qualification of lower activation materials for PROTO

⟨ Improved economy in electricity production

⟨ Improved low activation materials

⟨ Demonstration of a reference low activation steel forDEMO⟨ Search for higher performance materials for PROTO

⟨ Demonstration of waste management and recycling

⟨ Demonstration of safety management

⟨ Demonstration of low environmental impact potential

0 10 20 30 40 50

Years after decision on Next Step

DEMOAccompanying

Programme in Physics &

Technology

Design Construction Operation Applicationof results

PROTO (1.5 GWe)

Large Scale electricity production

(2 GWth)

Step (1/2 GWth)

Material Development

Environ. & Safety

From: Five year assessment report on the specific programme:Nuclear energy covering the period 1995-1999; June 2000

Starting point and reference scenario

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Conclusions 1/7

„The ITER project is the essential step towards energy production on a fast track.“

• engineering design finalized; modest upgrading over life of ITER • fully exploiting the flexibility of the present design: - tests of breeding and energy extraction - blanket modules prototyping the blanket for DEMO • demonstrate technical feasibility of fusion power on 20-30 year time scale

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Conclusions 2/7

„...in a fast track approach, the DEMO and PROTO generations could be combined in a single step...“

This power plant • has to be designed as credible prototype for power-producing fusion reactor• must not be fully technically and economically optimised• depends strongly on the development of adequate materials

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aims and milestones (K. Lackner, EFDA)

2. power into grid:

• DEMO & 1st generation power plants (economically competitive)

• DEMO & 1GPP will be based on similar/identical physics & technology

3. further improve economic & environmental properties • „advanced“ power plants

• R&D now, due to long lead times (materials)

• ongoing physics research

H. Bolt, 20.04.23

Next

Tentative Roadmap of Achievements starting from the decision to construct the Next Step

Main Achievements Required

⟨ Production and control of long pulse-burning plasma

⟨ Heat and particles exhaust (plasma facing components)

⟨ Test of breeding blanket modules for DEMO

⟨ Net electricity production (full hot breeding blanket)

⟨ High reliability of operations

⟨ Qualification of lower activation materials for PROTO

⟨ Improved economy in electricity production

⟨ Improved low activation materials

⟨ Demonstration of a reference low activation steel forDEMO⟨ Search for higher performance materials for PROTO

⟨ Demonstration of waste management and recycling

⟨ Demonstration of safety management

⟨ Demonstration of low environmental impact potential

0 10 20 30 40 50

Years after decision on Next Step

DEMOAccompanying

Programme in Physics &

Technology

Design Construction Operation Applicationof results

PROTO (1.5 GWe)

Large Scale electricity production

(2 GWth)

Step (1/2 GWth)

Material Development

Environ. & Safety

From: Five year assessment report on the specific programme:Nuclear energy covering the period 1995-1999; June 2000

Starting point and reference scenario

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Conclusions 3/7

Fusion landscape in Europe (medium term)

Emphasis of research on ITER:demonstration of sustained fusion power production and extraction

Fusion associations should concentrate on accompanying ITER R&D and plasma physics

Stellarators and Spherical Tokamaks should address possible improvements of concepts and of designs for future fusion reactors

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Conclusions 4/7

Materials

• solutions for a sustainable, environmentally benign and economically attractive energy technology

• ITER provides essential information on plasma facing materials

• high intensity neutron source such as IFMIF (Int. Fusion Materials Irradiation Facility): test and verify material performance in reactor relevant neutron environment

• before starting IFMIF engineering design: identify possibilities of relevant studies on Neutron Spallation Sources

• IFMIF engineering design should be completed during FP6 (until end 2006)

• modelling of radiation damage and structural evolution is instrumental to understand and control underlying processes.

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Conclusions 5/7

Elements of key importance

• construction of ITER as soon as reasonably achievable next step: extend mandate of negotiations to address cost sharing and site dependent issues

• ITER and IFMIF should proceed in a co-ordinated way: realisation of ITER starting in parallel with detailed engineering design of IFMIF

• existing facilities, esp. JET: not to be interrupted abruptly, but to be phased out progressively according to the schedule of ITER realization and the availability of financial resources (JET)

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Conclusions 6/7

Financial resources

• additional resources needed in the early stages (<2011) due to parallel progress of ITER and materials R&D• expand international collaboration• clear position of Europe should generate positive response also from potential ITER partners

long term: much less public funding required, if one generation of fusion devices can be saved

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Conclusions 7/7

Role of industry

• role of industry in the engineering of fusion devices should grow significantly during the realization of ITER and later of DEMO/PROTO

• involvement of utilities should increase progressively

• to drive the programme most efficiently towards power production: industrial sector has to assist in managing all phases of the programme; this also ensures that fusion developments meet industrial requirements for energy production

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Roadmap

EFDA reference case

3 years

demonstration of the feasibility of fusionpower generation

ITER

IFMIF

DEMO/PROTO

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Summary „fast track“

ITER: reactor-like fusion performance (moderate extrapolation to power reactor operation) successful extraction of reactor grade heat and tritium from blanket modules

materials: ensure industrial availability of materials which are ready to be licensed for use (80 dpa)

technology: industrial readiness in detail

fusion power generation feasible in 20 (25) years all elements to build first fusion power plant (DEMO/PROTO)

on basis of DEMO/PROTO operation: enter phase of large scale electricity production

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superconducting coils

vacuum vessel

blanket

structural materialsplasma facingmaterials

ITER

Materials for fusion reactors beyond ITER

10 m

Reactor (DEMO/PROTO)

10 m

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structural material

Baseline: ferritic-martensitic steel (EUROFER, F82H)

Composition (%)C 0.12, Mn 0.4, Cr 9, V 0.2, W 1.1, Ta 0.1

no Mo, Nb reduced activation

neutron irradiation:- dimensionally stable (data of similar steels up to 150 dpa)- no high temp. embrittlement

but: low temp. embrittlement

irrad. to 12.5 MWa/m2 FZ Karlsruhe

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structural material: needs

Baseline: ferritic-martensitic steel (EUROFER, F82H)here water-cooled Li-Pb blanket as baseline

to be done (EUROFER):

1. optimisation of composition and purity from strongly activating elements:

one, max. two further heats needed

2. proof of stability under fusion relevant neutron irradiation to high dose (80, 150 dpa);

esp. assessment of lower operation temperature to avoid embrittlement

improvement of plant efficiency (decreasing degree of readiness):

1. ODS-EUROFER: strengthening by oxide nano-dispersion allows upper operation temperature

of 650°C (presently 1st generation for fusion, experience from FBR available)

2. SiC-SiC composite „liner“ inserts to extract 800°C heat (non-structural application of

SiC-SiC appears feasible)

3. He-cooled plant designs become important, if SiC-SiC composites are mature for structural applications

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Neutrons - irradiation damage - neutron source

Fusion neutrons cause displacement damage and He-productionimportant for relevant studies: - relation of dpa to He (H) production- high neutron flux (target 25 dpa/year)

• fission sources low energy (<2 MeV): mainly displacement damage

• spallation sources

• D-Li stripping source

under planning: IFMIF

Fissionsources

FZ Karlsruhe

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Neutrons - irradiation damage - neutron source

Can material irradiations in spallation sources support fusion studies?

• How close can irradiation conditions be be brought to fusion situation?• Bracketing of fusion conditions by fission reactor irradiations and spallation source irradiations?• Capability of advanced modelling of radiation effects and structural evolution to fill bracket?• Would this approach be sufficient for licensing of materials?

Working group is being established within EFDA-frame

Neutron flux distribution in long pulsetarget region of ESS (FZ Jülich)

N/cm2/s

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Plasma facing materials: key issues

Key issues• erosion lifetime and plasma compatibility• neutron damage

• control of power deposition: to be established in ITER

• heat removal • fabrication technology

first wall:

modest flux of high energy neutral particles (100s eV),

low energy ions

divertor target:

high heat flux 10 (20) MW/m2

transient heat loads:

e.g. ELMs, disruptions

bulk plasma:

impurity tolerance

W < 2 10-5, reactor < 10-4

Be, C: 10-2

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Plasma facing components, lifetime (erosion of materials)

First wall: Erosion of low Z materialsorder of 3 mm/burn year: 15 mm in 5 yearstungstenorder of 0.1 mm/burn year: 0.5 mm in 5 years

0.01

0.1

1

WBe

Chot

CRT

Total erosion yield (C/D)

Deuterium impact energy (eV)10 100 1000 10000

Divertor:mostly redeposition of eroded wall material

D ions

Presently: order of magnitude-knowledge; data from ITER needed to assess PFM thickness

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Plasma facing components, plasma compatibility of tungsten

high operational flexibility, W-concentration in plasma <10-5

The tungsten programme in ASDEX Upgrade

tungsten coated divertor(500 m plasma spray coating)

W coated inner wall(1.5 m plasma PVD coating)

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Plasma facing and heat sink materials: research needs

ITER: establish quiescent plasma operation; learn to reduce divertor heat load by impurity seeding;

erosion data (apply relevant materials); resolve T-issue Satellite experiment(s): explore alternatives not possible in ITER

Materials development; mainstream: plasma facing material: thin functionally applied high-Z material divertor heat sink:: Cu-based derivates from ITER R+D: high neutron dose

first wall heat sink: ODS-RAFM, RAFM

Long term development; innovation: composites (MMCs, CMCs), ductile refractories, ideas (heat pipes,...)

Neutron damage: relevant n-irradiation facility for PFM, heat sink material and PFC development

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Status: Fusion Materials

• baseline materials for fusion reactors are within reach (e.g. EUROFER, W)• baseline technologies (esp. bonding, joining) have been developed for ITER

• neutron irradiation facility needed for materials assessment under fusion relevant conditions; accompanying modelling effort

• long term materials development should further increase attractivity in terms of environmental benignity, thermal efficiency, cost of electricity