Fusion for : Fusion Sources for the development of Fusion Energy

M. P. Gryaznevich Culham Science Centre, Abingdon, UK

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 1 - Fusion Reactor as an Advanced : F4N Concept

• High-output neutron sources (NS) are required in fundamental science and in many modern special and innovative technologies,

- and by nuclear industry to support energy production by cleaning waste and breeding fuel, or as a core of a new generation reactors

• In near term, DT fusion may become the most powerful NS. To date, have already demonstrated 5×1018 n/s @ 14.1 MeV in DT reaction and 5×1016 n/s @ 2.5 MeV in DD reaction.

• Super Compact Spherical Fusion Neutron Source can become a most intense Neutron Source today

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 2 - World Energy Crisis

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Fossil Energy

• Most of the world energy production is based on fossil carbon fuels: oil, gas, coal • Growing demand - India, China, newly developing world • Oil Peak has happened, gas underpriced • Climate change demands carbon-free energy • Environmental Pollution • Politics

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Existing Alternatives

Renewable energy (wind, wave, solar, hydro, biofuels) is an attractive option at present and offer long term, clean energy reserves. However : • Low energy density and still expensive • Fluctuates in time requiring storage systems

• Can not satisfy large fraction of energy demand (solar – 6GW in 2008)

• In some cases, bad environmental impact, at expense of food production (biofuels)

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Nuclear Energy (fission) • Existing 442 Stations: - produce ~20% of world electricity - in > 30 countries - up to 80% in some countries (France) • About 45 reactors are under construction, hundreds of new plants planned • Safe, clean, relatively inexpensive, but 3 problems: 1. Long lived radioactive waste products (many thousands of years) that require transportation, storage and re-processing, must be taken care of 2. Emerging uranium fuel shortage 3. Public concerns on safety and proliferation

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 We hope, no!

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 What is the Solution for Safe, Clean and Unlimited Energy Source?

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 IAEA

...occurs when two light nuclei are forced together, producing a larger nucleus The combined mass of the two small nuclei is greater than the mass of the nucleus they produce The extra mass is changed into energy We can calculate the energy released using Einstein’s famous equation: E = mc2 1kg of fuel would supply the same amount of energy as 1,000,000 kg of coal! 10 g of Deuterium (from 500 litres of water) and 15g of Tritium produces enough fuel for the lifetime electricity needs of an average person in an M Gryaznevich, Fusion Overview, Assessment of Programmeindustrialised on Thailand, Pathum Thani, Thailand, country!! 18-19/08/2008 - 9 - Nuclear Fusion Dream

• Sun on Earth: Controlled Nuclear Fusion Virtually unlimited fuel supply Deuterium from water + Tritium from Lithium • No long lived radioactive waste • 50 years of R&D, tremendous progress in the last decade • Controlled Fusion reaction demonstrated on JET (UK) and TFTR (US)

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 • 16 MW produced Fusion power in JET more than 10 years ago! (1991, 1997) • so it works and in TFTR (1994)

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 The Beginning of Fusion The 1946 Thompson, Blackman patent for a Fusion Reactor “..a powerful neutron source …. Also a powerful source of heat”

Based on a toroidal Pinch ZETA at Harwell, 1954-1968 : Parameters were modest: R / a = 1.3m / 0.3m, Ip = 0.5MA R/a=1.5m / 0.48m, Ip = 0.1 – 0.9MA classical confinement was assumed : Confinement was highly anomalous: t = 65s → T = 500keV t ~ 1ms → T~ 0.16keV Hence D-D fusion would be achievable - Beginning of a long path to Fusion Energy!

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 What is Fusion Power Plant ?

- Bass Pease, 1956 Deuterium Helium inside:

Tritium neutron

Tokamak

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 What is the TOKAMAK ? • Tokamak, from the Russian words: toroidalnaya kamera and magnitnaya katushka meaning “toroidal chamber” and “magnetic coil” Tokamak is a toroidal confinement device with: – Toroidal Field coils to provide a toroidal magnetic field

– Transformer with a primary winding to produce a toroidal current in the plasma – The current generates a poloidal magnetic field and therefore twisted field lines which creates a perfect “trap” – Other coils shape the plasma

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011- 14 - 22 September 2006 World Fusion Activities:

59 tokamaks are operational (plus , pinches, ) 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 10 under construction • International magnetic fusion research budget is 1-2 BEuro/year • ITER funded by International co-operation (10 BUSD)

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Magnetic fusion experiments around the world

Experiments all over the world progress the understanding of plasma physics and improve plasma performance and confinement.

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Q = When? Fusion Pulse Power duration Pout/Pin

1997 16MW ~1 sec <1

2018-2026 500- <30 mi n >10 700MW

~2050 (?) ~150- ~1 day ~50 2000MW

Steady progress, but long way…

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 New approach:

• At the IAEA Fusion Energy Conference at Geneva in 2008, Russia, China and US announced that Fusion science and technology are developed enough for construction of fusion-fission reactors that are able to clean (transmutate) nuclear waste and produce (breed) nuclear fuel from the spent one. • This is much faster way to commercial fusion compared with the traditional “pure fusion” approach for electricity production.

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Fusion Role in Nuclear Energy Production • Nuclear fusion reaction produces high-energy neutrons, which can be used to: - Recycle high level nuclear waste from conventional reactors into new fissile fuel or low-radioactive waste - Produce enough fuel to top-up fission reactor - Produce energy and tritium for self sufficiency • Combination of “fission + fusion” reactors becomes self- sufficient and environmentally clean, which dramatically improves both the safety and economics of nuclear energy production • Fusion with 60 years of R&D is now ready to help in resolving main problems of Nuclear Power production: fuel, waste, proliferation

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Fusion for Energy: 3 options

• “Pure” Fusion: ITER – DEMO – Power Plant • Fusion core for “hybrid” reactor, i.e. Fusion driven Subcritical • Fusion as a Neutron Source, or “F4N”

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 20 - Challenges for Fusion

•• Energy Energy production:production: commercialisation: commercialisation: - -Pure Pure Fusion Fusion (ITER (ITER line): line): 5050 –– 100100 yearyear targettarget - -Hybrid Hybrid for for energy energy production: production: samesame oror lessless (?)(?) - -Fusion Fusion for for closing waste transmutation: nuclear fuel cycle: today today •• 3 3 stages stages of of Fusion Hybrid PowerFusion Development: Power Development: - -compact Compact neutron neutron source source for for fusion fusion-driven-driven systems systems - -Multi Multi Functional Functional Tokamak Tokamak Reactor Reactor Prototype Prototype - -commercial Commercial Fusion Compact or FusionFusion--FissionFission Reactor Tokamak produces a lot of neutrons – construction of reliable neutron source (F4N) in the nearest task for Fusion development

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Neutron Sources

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 22 - Thermal neutron flux available at various neutron sources as a function of time since Chadwick’s discovery of the neutron

IAEA-TECDOC-1439

Spherical Tokamak SCFNS

 Since 1970 reactor sources are close to saturation of the flux reached  sources have overcome reactors in 90s, but flux growth is rather slow  Tokamak FNS reaching 1020 n/s may become the leader

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 23 - Most powerful neutron sources in the world (* - projects)

NS Type Facility Deposited Rate, 1017 Neutron Max. relative price of (location), Power, MW n/s Power Neutron Flux neutrons (from used nuclides S/S (Peak) S/S (Peak) Output, MW Density, UT report) S/S (Peak) n/cm2s

1. Fission ILL (Grenoble, France), U235 56 10 1.5 1015 reactors 3 PIK (Gatchina, Russia), U235 100 20 3 4.51015 IBR-2 (Dubna, Russia), Pu239 2 (1500) 0.6 (500) 0.03 (25) 1016

2. Accelerators SNS (ORNL), p, Hg 1 (30000) 1 (30000) 0.3 (10000) 1016 10 LANSCE (LLNL), p, W, Pb, Bi 0.1 (10000) 0.1 (10000) 0.03 (3000) 1016 *IFMIF (being negotiated), D, Li 9 1 1 1015 3. Tokamaks JET (Abingdon, UK), D, T 0 (16) 0 (60) 0 (13) 1013 1 *JT-60SA (Naka, Japan), D 0.01 (0.5) 0.01 (2) 0 (0.4) 1011 *ITER (Cadarache, France), D, T 500 1800 400 41013 *SCFNS, D, T 2-3 6-10 2-3 >1014

4. Inertial fusion *LIFE (LLNL), D, T 1000 (2100) 800 1017

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 24 - Fusion Reactions Fusion requires high plasma temperature, density & confinement

D - D fusion D + D → n (2.45 MeV) + 3He (0.82 MeV)

D-T fusion D + T → n (14.06 MeV) + 4He(3.52 MeV)

Other reactions possible, but have not been demonstrated in fusion devices at commercially required level

Fusion produces 14 MeV or 2.45 MeV neutrons. Variable energy output is also possible

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 25 - Challenges for “Fusion for Neutrons”

… to be competitive with other neutron sources:

Free neutrons thermal n-flux > 1015 n/cm2s Transmutation n-source rate > 1018 n/s Fuel breeding n-source rate > 1020 n/s - and many applications require much less neutrons (<1014n/cm2s), i.e. diagnostics, isotopes, research etc.

Compact tokamaks with a few MW fusion power may compete with contemporary neutron sources (fission reactors and spallation neutron sources)

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 26 - Fission & Fusion Neutron Sources

Most powerful neutron source based on nuclear reactor gives the same useful neutron production rate as a 3 MW fusion neutron source.

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 27 - What else Neutron Sources can do?

Neutron Source is a nice device to show where the atoms are… … and also a nice device to show where you can get a Nobel Prize! M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 28 - Fusion Neutron Sources

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 29 - Options for Fusion Neutron Source

• Auxiliary heating, T consumption and magnetic systems set the cost of a demonstration experiment Running costs • Classical tokamaks R/a > 2.5: > $500 M/year-100% - superconducting coils are possible for providing high TF ~6 T, but leads to high T consumption (big device size) Capital cost as low as $50M • Spherical tokamaks R/a < 2.0: Running cost < $50 M/year-100% - copper coils with water cooling are possible, only power dissipation (running costs) constrains TF in ST FNS - stress limit (TF) favours the lowest aspect ratio - high beta in ST ensures no physics limitations - neutron balance of ST is optimal at R/a ~ 1.6

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 30 - Fusion Reactor as an Advanced Neutron Source FDF • Many proposals of FNS have been considered: - conventional tokamaks: FDF (Stambaugh); ITER- type (SABR Stacey, Rebut); FDS-1 (Wu); FEB (Feng) - mainly considered as prototypes of fusion-fission hybrids - superconductive (big, expensive to build) or Cu (pulsed, high operating costs) - need to breed tritium FDS - high divertor and wall SABR load, high NB power - rely on ITER technologies FEB-E

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 31 - Can we improve the tokamak?

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 25 Years of ST Research Prototypes of a Compact Fusion Neutron Source

MAST, START and about 20 other STs around the World

In operation, 1991

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 33 - as an Advanced Neutron Source Intensive studies during last 15 years

R/a, m Ip/Bt, kA/T k Pin/Pfus MW VNS UK 0.8/0.5 13.4/3.5 2.3 69/32 CFT UK 0.85/55 6.5/2.5 2.4 44/35 CTF US 1.2/0.8 12/2.5 3.2 47/150 CFNS US 1.35/0.75 14/2.9 3 50/100 STEP UK 1.2/0.75 5/3.5 3 40/30 JUST RF 2/1 5.3/3.9 1.6 45/62 FDF China 1.4/1.0 9.2/2.5 2.5 19/100 STPP US 0.7/0.5 11/3 3 30/300 CVNS UK 0.57/0.35 6.8/2.5 2.3 25/16 TIN RF 0.47/0.28 3/1.35 3 15/2 CSTPP US 0.47/0/28 14/9.6 3 50/310 SCFNS UK 0.5/0.3 1.5/1.5 2.75 6/2 Texas CFNS, US FDS-ST, China US CTF, Peng JUST, RF UKAEA CTF

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 34 - Super Compact Fusion Neutron Source

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 35 - Mission of Super Compact FNS

• To show feasibility and advantages of the ST concept as a powerful neutron source • To demonstrate and use steady-state fully non-inductive regime • To operate with tritium, contributing with this to the mainstream Fusion research in many areas (T handling, material/component testing, diagnostics, safety, remote handling etc.) • To be the first demonstration of possibility for commercial application of Fusion today

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 36 - Strategy for Design Work

Diagram of Design Options

Research: MA burner: Small ST, 20-50 MW, long no pulse SCFNS neutrons, HTS option Core Design:

less Power R=0.5 m, 2-5 MW more Power steady state DT SCFNS breeder, Medical isotopes, transmutator etc: diagnostics, research: >100 MW high-Q CFNS, s/s or 5-50 kW SCFNS, pulsed DD, s/s or pulsed

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Simplest SCFNS • Main SCFNS parameters, mainly interpolation:

R/a = 0.5m/0.3m, k = 2.75, Ipl=1.5MA, Bt=1.5T, PNBI ~5-10MW, ENBI ~100-130keV - Size: between START and MAST. Same as QUEST, Pegasus - Elongation: NSTX/MAST-U - Plasma current: NSTX/MAST-U level. Three times higher toroidal field - NSTX/MAST-U heating power, but up to two times higher beam energy 2 Useful test area ~ 10 m ; fusion rate Be, D O, 1018n/s thermal rate 5x1014 n/cm2s (up Cu/Be 208Pb, 2 238 C 15 2 U to10 n/cm s)

Be shielding

Inner vessel TF coils

Outer vessel

Divertor coils NBI ports PF coils

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 38 - Other Super Compact designs

• Analysis of two ST FNS designs closest in size (R < 0.6 m) confirm feasibility of SCFNS

UKAEA VNS, T C Hender et al, FED 45 (1999)

R = 0.57 m, Bt= 1.5 T, Ip= 6.8 MA, k = 2.3, PNB= 25 MW

GA ST Pilot Plant, R Stambaugh et al, FT 33 (1998)

R = 0.47 m, Bt= 9.6 T, Ip= 14 MA,

k = 3.0, PNB= 50 MW

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 39 - General Atomics ST Pilot Plant • Motivation for compact GA ST confirms feasibility of ST path to commercial application as an FNS: - ST approach can progress from Pilot Plant to Power Plant just by doubling or tripling the linear dimensions of the device with no changes in technology - ST approach has the two key features of an executable commercialization strategy: - a low-cost pilot plant that can attract commercial cost sharing at an affordable level and with minimal financial risks; - and a strong economy of scale leading to compact Power Plants - The fact that a viable concept for a Pilot Plant exists is the principal attraction to government of the compact ST approach to commercial transition.

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 40 - Advantages of High Magnetic Field in FNS

2 4 • Fusion power from DT thermal reaction PFUS~ b B • MAST results confirm good prospects for beam- plasma DD reaction • Plasma energy confinement in ST ~ B1-1.4, so better prospect for heating and current drive • Stability improves at high field • Better prospects for RF heating and current drive • Overall: higher field – cheaper neutrons (also better prospects for energy production) Recent development of a new generation of High Temperature Superconductors (2G HTS) opens promising opportunities for high field magnets in STs.

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 41 - New ideas – High Temperature Superconductors (HTS)

• The recent development of „High Temperature‟ superconductors could have far-reaching application. • They give similar performance to LTS but at around 77K (liquid nitrogen) rather than 4K (liquid helium) temperatures.

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 First Result of HTS Coil Tests on Tokamak GOLEM Prague, August – October 2011 (in a scope of IEAE Coordinated Research Project F1.30.14 “Utilisation of a Network of Small Magnetic Confinement Fusion Devices for Mainstream Fusion Research”)

Tokamak Solutions UK In collaboration with: Oxford Instruments, Technical University of Prague, IPP Prague, Forma Machinery LV

Cryostat installed on Golem tokamak

Nitrogen coming out through ventilation holes during plasma pulse 43 M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 First Tokamak with HTS Coils

New HTS coils

LN HTS

6 turns 0.1x12mm tape Kapton isolation Small tokamak GOLEM ~1x12mm coil at Technical University of Prague

44 M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 First Tokamak with HTS Coils

Upper PF coil cryostat winding the coil filling with liquid nitrogen

Power Supply LN Supply

45 M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011

First Operations of a Tokamak with HTS Coils

resistivity

time Superconductivity achieved! Plasma pulse with 0.3kA in HTS coils

First tests on 29/08/2011 First tests with plasma 28/09/2011 Maximum current of 1kA achieved on 29/09/2011 46 M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 Super Compact Fusion Neutron Source (F4N) Concept is based on the latest developments in Fusion and & Technologies

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 47 - How will we build the SCFNS?

• The engineering is now standard practice in fusion laboratories and with their component suppliers, but now needs to be brought to commercial levels of reliability, safety, cost and volume. • 20 prototypes of the CFR, which is based on the novel spherical tokamak design, are currently operational. • The construction venture will work with the current best suppliers and industries from several countries, including Hitachi, Toshiba, Mitsubishi, Fuji (Japan), Northern Plant, Efremov (Russia), Princeton (US), Culham (UK).

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 48 - How will we build the SCFNS?

• 20 Spherical Tokamaks built in last 15 years by leading Nuclear and Fusion Industries CPD, TOSHIBA, Japan, 2005 PF coils Vacuum PF vessel coils TF coils

EF coils Globus-M, North Plant, Russia, EF coils PF coils

2000 ST plasma UTST, Fuji, Japan, 2008

QUEST, TOSHIBA, Japan, 2008 KTM, Efremov Institute, Russia, 2007 M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 49 - How will we build the SCFNS?

Both VV and TFC are changed after reaching the fluence limit or in a case of accident Changing the vacuum vessel and TF coils

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 50 - CONCLUSIONS

• High-output Neutron Sources are required in fundamental science and commercial applications, including isotope production and nuclear industry

• In near term, DT fusion may become the most powerful NS

• FNS with Mega-Watt rates (1017-18n/s) will have strong influence on the global energy production strategy as well as on the development of fusion & nuclear science and technologies

• Compact ST may become the most efficient and feasible Fusion Neutron Source and an optimal core for a fission-fusion hybrid

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 51 - CONCLUSIONS

• Development of a steady-state reliable Neutron Source in the nearest task for Fusion

• The ST path to commercial application of Fusion can start from a Compact ST with R as low as 0.5 m and NBP 5-10 MW

“It seems important to have an achievable goal in the not too distant future in order to encourage the large goal, in this case pure fusion” H Bethe, Physics Today 1979

M Gryaznevich, Lecture at Technical University of Prague, 19 October 2011 - 52 -