Path to Fusion Power: new look in ITER era Role of Small Fusion Devices in Today’s Fusion Research

1. Progress on Joint Experiments on Small Tokamaks and other Activities within the IAEA CRP on “Joint Research Using Small Tokamaks” M Gryaznevich1 , E. Del Bosco2 , G. Van Oost3, A. Malaquias4, G. Mank4 for the CRP “Joint Research Using Small Tokamaks” team 1EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, UK 2 INPE, São José dos Campos, Brazil 3 Department of Applied Physics, Ghent University, Ghent, Belgium 4IAEA, NAPC Physics Section, Vienna, Austria 17th IAEA TM on Research Using Small Fusion Devices Instituto Superior Tecnico, Centro de Fusão Nuclear Lisboa, Portugal 22-24 October 2007 This work was funded by the IAEA Technical Contract No: 12941 / R0

2. Talk Outline and issues to address Path to Fusion Power: new look in ITER era Role of Small Fusion Devices in Today’s Fusion Research Activities within IAEA CRP “Joint Research Using Small Tokamaks” - Joint Experiments - progress in the CRP database and in international collaborations Small Tokamak Activities Beyond the CRP

3. On the path to fusion power • “Fast Track” (Professor David King et al): 20-30 years • 1. ITER and IFMIF in parallel, – the top priority and on-going • 2. Early DEMO • 3. Commercial fusion plant • Use ST, stellarator etc (and inertial fusion) as/when appropriate • How to accelerate/reduce risks for the commercial exploitation? • Continue research on present facilities to progress Fusion science and Technology • Add devices (e.g. beam facilities for materials, multiple DEMOs, advanced concepts) - One such device is a Component Test Facility (CTF), to assist DEMO • Test macroscopic assemblies/prototypes with welds, brazes, composites, with realistic cooling etc at high neutron flux and fluence (and gradients). • Test plasma facing components • Demonstrate commercial applications of Fusion Power asap (now)

4. “Super - Fast Track”: commercial power plantin 8 years • Main issues: • - minimise wall load (until wall/divertor problems resolved by ITER, IFMIF and CTF and new materials arrived/tested) • - reduce fusion output by 10 -100 times (keeping Q > 5) • - minimise blanket mass to reduce “mass inertia” (pulse operations) • - extend power plant capabilities to tritium and hydrogen production (or even hot water for central heating), i.e. maximise commercial output • - transmutation? – may be a big push for commercial application • A conventional tokamak with a multi-purpose blanket, or a medium-size ST with NB heating (no a-particle heating) and a hybrid blanket/test modules as an option • New physics is key to success – traditional “mainstream” tokamak regime is little help (… but fusion already demonstrated: JET, TFTR) • New technologies must be implemented in a 21st - century tokamak • - use latest developments in technology

5. Path to fusion power: new physics R/a = 1.0m/0.7m

6. Path to fusion power: new technologies • Low recycling for new confinement regime requires new wall materials (liquid metal?) or new pumping/pressure control approaches • Increase in toroidal field in ST requires new toroidal magnet design (high temperature superconductors as an option) • Start-up and CD in ST requires development of RF technology • Replacement of a-particles as the main heating source by NBH requires development of low-energy (<100keV) steady-state NBI

7. Neutral beam ~7m Ultra Compact Power Plant – a “small tokamak-reactor” • R ~ 0.75m, a = 0.47m • A = 1.6 • Ip ~ 4MA • < 20MW fusion power • Q>5(50 with hybrid blanket) • neutron flux~0.5MW/m2 • ~1kg T/yr • Low construction and running costs • This compact version is challenging… • … but based on known physics and developed technologies • See L Zakharov, “3 steps in Fusion Power Development”, APS-06 Invited talk

8. World Fusion Activities 54 tokamaks are operational (plus stellarators, pinches, spheromaks) Asia: 26 (14 in Japan, 5 in China) Europe: 15 (6 in Russia, 2 in UK, 2 in Germany) America: 12 (7 in USA, 3 in Brazil) Africa: 1 International magnetic fusion research budget is 1-2 BEuro/year ITER funded by International co-operation (10 BUSD)

9. World Fusion Activities: Update 2007 New tokamaks under construction: KSTAR, Korea (last month started ops.) QUEST, Kyushu University, Japan SST-1, India KTM, Kazakhstan TOKASTAR, Nagoya Univ., Japan, (first plasma) TEXT/HUST, US=> Wuhan Univ., China Proto-Sphere, Italy (former START, UK) COMPAS-D, UK=> Praha, Czech Rep. STOR-1, Canada=> Univ. of Utah, US, (first ops.) HT-2M, PRC=> Pakistan, MEDUSA, US => Mexico NOVILLO, Mexico (re-start) + possibly new tokamak at Beirut, Lebanon + possibly new tokamak in St Petersburg, Russia + possibly new tokamak at IC, London, UK Total auxiliary heating in small tokamaks exceeds 50 MW 54 tokamaks are operational (plus stellarators, pinches, spheromaks) Asia: 26 (14 in Japan, 5 in China) Europe: 15 (6 in Russia, 2 in UK, 2 in Germany) America: 12 (7 in USA, 3 in Brazil) Africa: 1 International magnetic fusion research budget is 1-2 BEuro/year ITER funded by International co-operation + W7-X + NCSX ITER

10. Why we need to carry on fusion research when we are constructing ITER and Power Plant? • Develop technologies, diagnostics, materials • Study/develop new advanced regimes for example, low-recycling regime can be tested on present devices (QH-mode on DIII-D, flat temperature profiles in STs) • Research on present devices provides training for scientists and engineers also faces many problems of future reactors even excluding specific physics: organisation, safety, security, remote operations, etc. • ITER may be not a DEMO-prototype, but JET/ITER design can be used in hybrids and compact power plants even now Continuality of research is very important!

11. What is the role of small fusion devices in the path to Fusion Power? • Develop technologies, diagnostics, materials • Liquid metals in ISTTOK, CDX/LTX, T-11M • Plasma processing, plasma-wall physics in AC operations (ISTTOK, STOR-M, HT-7M) • Remote participation, web tools, data processing, analysis • Education and training providing sustainment of scientific and engineering schools, expertise • New physics – new regimes (START, CDX-U, STOR-1M etc.) • General plasma physics – turbulence, reconnections, AE, other MHD. - Transport studies – limited, but START, COMPASS-D, C-mod contributed effectively - COMPASS-D: ELMs mitigation Continuality of research is very important!

12. What determines the role of small fusion devices in the path to Fusion Power? • ITER will outline needs for RUSFD, but it is necessary to look beyond ITER as well • Pulse reactor requires small size to reduce blanket mass/inertia • Need to reduce wall load for cycle fracture • Liquid walls/divertors (not foreseen in ITER) • “Generation gap” and geographic requirements determine education and training needs • EAST, KSTAR, KTM, SST-1 need hundreds of qualified staff • New physics – new regimes • Mainstream ITER regime requires little extra research, but advanced regimes, hybrid regimes can be studies on moderate-size devices (DIII-D, AUG) • General plasma physics – improves links to Universities, emerging sciences

13. Many of these issues are addressed to the co-ordinated research using small tokamaks in the scope of the IAEA CRP • New opportunities for small tokamaks: • Combined efforts within a network of small and medium size tokamaks provides further enhance contribution of small tokamaks • New concept of interactive co-ordinated joint research using small tokamaks in the scope of IAEA Co-ordinated Research Project (CRP), started in 2004, is a new step in better co-ordination of this collaboration and in improvements of links between small and large tokamaks

14. IAEA CRP on Joint Research Using Small Tokamaks: • Objectives of the Agreement (14 participants) are: • - to achieve a network of fusion research using innovative possibilities of small tokamaks • - to ensure deeper integration of small tokamaks in national, regional, and international fusion activities • - to increase the number of collaborative experiments • - to promote fusion research in developing countries and open wider possibilities for young scientists • Work packages for different research activities are carried out under supervision of members of CRP thus providing clear future perspective for small tokamaks in co-ordinated approach • This helps to improve the quality of scientific output from small tokamak research activities

15. Joint Research Using Small Tokamaks: • Present Activities: • - Informational Network, see www.fusion.org.uk/iaeacrp • - information, news, useful links • - small tokamak database • - list of activities, Joint activity matrix • - CRP Database (contains data from Joint experiments) • - Joint (Host Laboratory) Experiments • - 1st Joint Experiment: CASTOR, Praha, September 2005, • 2nd Joint Experiment: T-10, Moscow, Sept-Oct. 2006 • 40 participants from 14 countries • - 3rd Joint Experiment: ISTTOK, starts this week • - Collaborative and independent activities, visits, exchange of equipment, more than 30 joint publications since 2005, etc., with financial support via IAEA CRP • Please consider your participation !

16. Main achievements and outputs of JEs • First JE at CASTOR:"Joint Experiment on Edge Plasma Studies on the CASTOR Tokamak", August 28 – September 9, 2005, IPP Prague. • main achievement was that we have started the process! • also: • - good tokamak availability and infrastructure, diagnostics • - good team work • Scientific output was moderate but valuable (two publications, several presentations, including poster at IAEA FEC at Chengdu, October 2006)

17. Main achievements and outputs of JEs Second JE at T-10: "Joint Experiment on Investigation of Core, Edge and SOL Turbulence and Its Influence on Plasma Transport in T-10 Tokamak", September 25 - October 6, 2006, KIAE, Moscow, Russia. main achievement - valuable scientific results during experiment and extended scientific output (4 presentations at EPS Conference, Warsaw, July 2007, more publications and presentations expected) also: - good tokamak availability and infrastructure - extended diagnostics, including unique - good team work, more narrow specialisation - experience from work on medium-size tokamak, in particular for non-experts

18. Other achievements and outputs of JEs: • Opportunity to participate in CASTOR & T-10 experiments within international team was highly rated by most participants • Discussions with experts in major topics, knowledge and expertise exchange, exchange of information about domestic experiments and analysis tools, establishment of new links and collaborations. • Good organisation of experiments: • Full support and attention of the Host Institutions management, which resulted in: • Tokamaks and diagnostics readiness • well-prepared experimental plans • good group leadership with distribution of functions between group members - excellent team work • good organisation of daily operations, information on machine and diagnostics status, group leaders briefings before and after experiment. Workshop at the beginning was a good idea. • clear distribution of post-experiment tasks on data analysis, preparation of presentations and publications • brief reports prepared in short terms • well-organised accommodation, transport and social activities • 4. Scientific output is valuable, broad and immanent.

19. Main lessons from first JEs and ideas arisen 1. Some problems with data access at the beginning, poor documentation. 2. Log book with easy access and visible in control room, etc., is essential - to bring medium/large tokamak culture to small tokamak community (also preparation for ITER, other next steps) - this may be a criterium/request for next JEs 3. More information prior and after experiment – briefings, reports, tokamak parameters and regimes, list of available diagnostics. A section in training in the machine operation and data access should preceed experiment. 4. List of participants should be available at the start of experiment. 5. Communication skills of key persons should be sufficient. 6. Proposals and suggestions for better organisation of future JEs. Formulate criteria for suitability of the host. 7. Better timing of JE, link to the local and international constrains. 8. More information on CRP during JE. Preprints, reports. 9. Remote participation in experiment, remote data access, video-conferences etc.

20. Proposals and ideas for next Joint Experiments • and other activities during the last year after the end of the CRP in 2008 • progress in the CRP database, web page and remote participation tool (IST) • propose possible Technical Contracts • preparation of a new CRP, which will reflect: • recommendations from the final RCM • experience from Joint Experiments • established links and collaborations within the small tokamak network • needs for RUSFD, outlined by ITER guidelines and requirements for R&D in connection with the fast track Fusion programme • It will be necessary to establish closer contact with ITER team and other Institutions (ITPA, EURATOM, EFDA, DoE, Japanese Office of Science, IEA, etc) to make RUSFD better co-ordinated within the World Fusion activities

21. Proposals and ideas • for next Joint Experiments • 1st JE at CASTOR: first attempt, experience, training in tokamak operation and diagnostics, team work • 2nd JE at T-10: extended programme, team work on medium-size tokamak (closer to big tokamak environment), more scientific results obtained during experiment, more publications

22. Proposals and ideas • for next Joint Experiments • Next JEs should be logical continuation of the first three • Next JEs should maximum use experience of previous experiments • They should be a step forward and sustain achieved high quality • They should add some new scope to the JE and bring new ideas, not just repeat what was done at different tokamak • Venue: Brazil – joint experiments on two participating tokamaks • Russia (Ioffe, SPS University) – joint experiments on three participating tokamaks • or TEXTOR, Germany, to enhance links with EFDA and co-ordination within EURATOM programme