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Fusing the World: ITER – fusion energy in 50 years?

Fusing the World: ITER – fusion energy in 50 years?. Fusion energy rules!. In fact… Practically all energy consumed by people is fusion energy – from the Sun. The only major exception is fission that releases energy stored from supernova explosions.

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Fusing the World: ITER – fusion energy in 50 years?

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  1. Fusing the World:ITER – fusion energy in 50 years?

  2. Fusion energy rules! In fact… Practically all energy consumed by people is fusion energy – from the Sun. The only major exception is fission that releases energy stored from supernova explosions. In the sun, the plasma fuel (hydrogen) is confined by gravity, and the energy producin reacton is 4 protons 1 Helium + energy

  3. So why not produce fusion energy on Earth?Would be badly needed ...

  4. Population doubles Energy consumption get 2-3 folded Problems with easy fossil sources Additional capacity needed min 10 - 20 TW 50 40 30 20 10 0 Gtoe 185019001950200020502100 Energy forecast until 2050 • Potential candidates for • Additional capacity: • renewables (H2O, bio, solar, wind) • fission (238U, Th) • fusion

  5. Energy density:Fuel needed by a 1000 MWe power plant per year Nuclear power plant 30 tons of enriched Uranium (two truck loads) Fusion power plant 300kg D + Li eV vs MeV Coal fired power plant 2 400 000 tons coal (35 000 cargo vans) Wood burning plant 15 000 000 m3 logs How about not using fuel at all? • 80 km2 solar panels, or • 1000 MWe wind mills • back-up power production

  6. From the energy gain point-of-view, fusion is very attractive…

  7. Additional benefits • safe (read: hard to achieve…) • Environmentally benign (no pollution) • no greenhouse gases -> fights climate change • ash from nuclear burn = precious He -> not radioactive • does not produce materials for proliferation • fuel sources practically limitless: Deuterium and Lithium ( Tritium: n + Li  He + T) • Fuel sources ‘democratically’ distributed: • sea water -> D • earth crust -> Li

  8. Fusion on Earth • D-T fusion has the highest cross section at “reasonable” temperature • Coulomb wall ⇨ ‘reasonable temperature’ T = 100 000 000 C • DT-fuel = plasma -> fusion physics = plasma physics • Obtaining net energy from fusion reactions requires • Sufficiently high density n • Sufficiently high temperature T • Sufficiently high confinement time τE nTτE > a critical value D + T  4He + n + 100 000 kWh/g

  9. Measuring plasma performance: Plasma power balance: • Pout = Pfus + Ploss • Ploss = Pbr + Wth/τE For self-burn, plasma needs to be ignited Pin > Ploss: Pin = ηPout > Ploss ; η = efficiency η(Pfus + Ploss) > Ploss ηPfus > (1- η)Ploss

  10. Fighting for dominance • Pbr = αbrn2√T • Wth = 3nT ;(We + Wi) • Pfus = (n2/4)<σv>Qfus

  11. Lawson criterion Lawson Ignition Toptimal ≈ 25keV

  12. Reaching the criteria, Part I: ICF Maximize the pressure, nT  ‘inertial confinement fusion’ = confinement only by inertia of particles • First successful(?) experiment already in 1952: • Teller-Ulam H-bomb (ignited by a fission bomb • Proof of principle for inertial confinement fusion • More constructive use of ICF has been developed over the past 20y or so -> NIF at LLNL, USA Nice picture of an explosion

  13. Reaching the criteria, Part II: MCF = Maximize τ Charged particles glued to magnetic field lines ! • … unless the field is inhomogeneous and/or lines are curved • Reflection, trapping • … or the particles are exposed to external forces • Drifts (B×grad B, E×B, F×B,…) • Different geometries • Magnetic mirrors (1st attempt) • Stellarator • Z-pinch, • θ-pinch, • reversed field pinch • … and… The tokamak

  14. + With ferromagnetic steel inserts placed at the coils, the ripple can be minimized. = This improves charged particle confinement. Bf Reducing toroidal ripple: ferritic inserts A finite number of TF coils → non-axisymmetric field. The local magnetic “bottle” between two TF coils can trap charged particles, which quickly drift out of the plasma. Bf

  15. Tokamak, the Human Reactor TokamakBasics toroidal'naya kamera v magnitnykh katushkakh — toroidal chamber in magnetic coils Plasma confinement: • Strong toroidal field (by external coils) • Weaker (1/10) poloidal field (by plasma current) Helical magnetic field lines • Plasma heating: • Ohmic (Ip) • Neutral beam injection at high E • Radio frequency heating (ECRH, ICRH) Based on transformer principle •  Suits poorly continuous use… However: • various means of external current drive can facilitate continuous use

  16. Who actually confines what?-- duality in plasma physics Tokamak confinement from single particle point-of-view: • Charged particles gyrate around toroidal fieldlines = are confinened • Introduce toroidicity B-drift Ez  ExB-drift in R-direction  Need to short-circuit: • Introduce Bpol Tokamak confinement from fluid point-of-view: • Force balance: p = jxB • Tokamak based on induced current jtor • Confining field = Bpol !! Btor needed to stabilize the toroidal plasma ... In both cases the end result is helical field lines

  17. Tokamak and beyond:how to make dimensions disappear • Helical field lines ergodically cover closed flux surfaces  tokamak = “1D system” • Helical field lines can also be produced entirely by external coils  stellarator, geometrically a lot more complex but still with well-defined flux surfaces Stellarator configuration

  18. MCF works already!! ... or, well... works, does not work, works, does not work, works ....

  19. Progress in MW

  20. Progress in nTτE

  21. However: Past is easier to predict than future… Tokamak was a major breakthrough  Prediction: Tokamak to every home in 5 years ... However… Ohmic heating was not sufficient Auxiliary heating  10’s of keV, yes! … However … When T rose, the confinement dropped…  What a nice surprise?!? … Until … 1982 ASDEX tokamak in Germany L-H transition ! Sufficient confinement ! … However … In H-mode, the plasma started violently burping = ELMs (Edge Localized Modes)  Unacceptable (sporadic) power loads on PFCs … However … The ELMS efficiently flush out impurities (and He ash..) Mmm, turbulence and other nonlinear stuff

  22. Major Advances in fusion physics • From bottle to doughnut (design in 50’s, demo in ‘68) • L-H transition (experimental, ‘82) • DT experiments (90’s): • TFTR (1993): Pfus = 10.6 MW • JET (1997): Pfus = 16.1 MW (Q ~ 0.7) • Anomalous transport = microturbulence (theory, 00’s) • ITER = International Thermonuclear Experimental Reactor (construction during 10’s) Today, energy production by magnetic fusion can be considered scientifically verified. … In fact it works so well that in today’s experiments, mock fuel (DD) has to be used to avoid excessive activation of the device !!

  23. Fusion reactor = ”steam engine” - w/ burn temperature of 100 million C • Feed D-T gas to the reaction chamber and heat to fusion temperatures • Fusion burn • 3.5 MeV ’s maintain high temperature • 14.1 MeV n’s transport the energy released in fusion reactions out, and it is used to boil water • Cooled-down He ash is pump out via the divertor • More T is produced by fusion neutrons in the Li blanket surrounding the plasma • If anything goes wrong, the burn quenches

  24. Fusion research globally • Sun rises from the East: all *new superconducting* tokamaks are in Far East (China and South Korea), Japan constructing one • Europe seems to ’implode’: currently in leading position in fusion research but progress is being killed by bureaucracy • US politics so unreliable that researchers seem to have to rely on ’headline manufacturing’ at the cost of reliability

  25. Far East South Korea: KSTAR R = 1.8m a = 0.5m Ip = 2MA BT = 3.5T China: EAST R = 1.7m, a = 0.4m Ip = 0.5MA BT = 3.5T Japan: JT-60AS (SC) satellite tokamak for ITER R = 3m, a = 1.1m Ip = 5.5MA, BT = 2.8T

  26. Europe MAST Culham, England ’spherical tokamak’ R = 0.85m, a = 0.65m Ip = 1.3MA, BT = 0.6T ASDEX Upgrade IPP-MPG, Garching, Germany Specialized in PWI: high P/A R = 1.7m, a = 0.6m Ip = 5.5MA, BT = 3.1T JET Culham, England LARGE, high performance R = 3m, a = 1.3m Ip = 4.8MA, BT = 3.5T Additionally smaller, more specialized machines: TEXTOR (Germany), Tore Supra (France), TCV (Switzerland)...

  27. USA NSTX Princeton R = 0.85m, a = 0.68m Ip = 1.4MA, BT = 0.3T DIII-D General Atomics R = 1.7m, a = 0.7m Ip = 2MA, BT = 2.2T

  28. Will electrons powered by fusion ever reach my electrical outlet? • We do not know yet. • Open issues: • Dynamics of burning plasma: plasma physics • Continuous operation: technology • Controlling plasma wall Interactions (PWI): plasma physics + atomic and molecular physics + material physics + engineering In order to address these issues, the first reactor-scale research tokamak, ITER is currently under construction in Southern France.

  29. Mission: “to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes” Worldwide fusion project - ITER ITER partners • EU, India, Japan, China, Korea, Russia and US (= over half of the world’s population) ITER site and expenses • Cadarache, Southern France (European Site) • Building cost in excess of € 5 billion • Contributions 85% “in-kind” and 15% “in-cash” • EU share 50% (France 10%), others 10% each ITER agreement signed in Paris 21.11.2006 • Site preparations started 2007 • Constructions started 2010 • First (political) plasma foreseen in 2020 ITER fusion reactor: 500 MW with fusion gain Q > 10

  30. iter.org ITER is under construction in France With a machine costing ~15 billion € and producing about 100 MW of alpha power, it is very important to know where the alphas end up depositing their energy! ITER is the world’s largest international energy research project. Its goal is to demonstrate the scientific and technical feasibility of fusion by producing 500 MW of fusion power for hundreds of seconds at a time (Q~10).

  31. Hans the handyman is smaller than pipes! ITER specifications • Plasma conditions similar to expected power plant • Technical specs: • Total fusion power: 500 MW • Q = Fusion power/aux. heating power ≥ 10 • Plasma major radius: 6.2 m • Plasma minor radius: 2.0 m • Plasma current: 15 MA • Toroidal field at 6.2 m: 5.3 T • Plasma volume: 837 m2 • Installed auxiliary heating: 73 MW • Cost: 5 + 5 + 0.5 = 10.5 billion (building + operation + decommission)

  32. ITER reactor – main components Blanket elements (420 pieces) Auxiliary heating (RF, NBI) Fusion chamber Divertor casettes (54 pieces) Cryostat SC Magnets (18 TF, 6 PF, 6 CS) Vacuum chamber Cooling water pipes Yleismies Jantunen röörejä tsiikaamassa

  33. ITER construction site 2011

  34. ITER Construction site Dec 2012

  35. The Future? 50 years is a handy number  IFMIF = International Fusion Material Irradiation Facility • “Fast track” possible but a power plant unlikely before 2050 • Economical feasibility determined by DEMO, the next step after ITER:n • No shortage of fuel: • D ‘limitless’ • Li→T thousands of years • But the other materials = problem: first wall, divertor etc…

  36. And what about us Finns? Under Association Euratom-TEKES we entertain ourselves by engaging in the following activities : • multiscale modelling:Simulations from sub-microscopic level (behaviour of individual molecular bonds) to macroscopic level (wall loads in MW/m2) – SimITER Consortium by Academy of Finland • Information technology: new solutions, *innovations*, are needed to facilitate massive simulations • Engineering and technology:DTP2 in Tampere (TY&VTT) All work is strongly international: • All experiments are done at JET and ASDEX Upgrade

  37. Fusion at the crest of Aalto • Feisty particles at the ASCOT race track: • Fusion reactions and auxiliary heating produce ions in MeV range • a group of anarchists in a fusion reactor? • The Monte Carlo -based particle following code ASCOT can be used to reliably trace these particles all the way to the wall components •  hot spots?

  38. ITER surface loads: ASCOT Simulations • ASCOT = Accelerated Simulation of Charged particle Orbits in Tori • Particles followed in 2D/3D magnetic fields • Interactions/collisions modeled by Monte Carlo operators • F4E contract GRT-379: ITER wall loads • Fusion-’s, NBI particles, RF-heated ions • Magnetic fields needs to be calculated carefully! • ~100 000 ions / simulation • So called limiters take most of the heat • Results needs to be well-validated; the cost of an error can be 0.5 million € Wall & divertor load Limiter load

  39. Aalto <-> VTT flows • All energy leaks have to be fixed in a reactor: • Microturbulence has to be quenched !! • ELMFIRE – a full-f gyrokinetic code for turbulence Very challenging theoretically and computationally Lin, Science 281 (1998) 1835

  40. “Cost” of the simulations • Comparison to CGI & SFX: • Toy Story (1995): 800 000 CPU-hours = 91 CPU-years • Titanic (1997): < 100 CPU-years • Star Wreck: In the Pirkinning (2005): < 10 CPU-years • 3D ASCOT simulation: ~4 CPU-month • ELMFIRE-simulation: > 1 CPU-year • 250 000 000 particles • 1 ms • Typical annual saldo: 100 CPU-years More nice explosions

  41. More fusion at Aalto: still surfing but not so hot ... Cleaning chores (global): • Impurities released from the chamber wall can not only contaminate the plasma, but also lead to retaining radioactive tritium • nuclear lisensing issue ! • Migration of impurities has been studied using the American DIVIMP code, but is now challenged by our ASCOT that can handle realistic 3D geometries

  42. Dirty work @ UH & VTT • Erosion & deposition of wall materials (= impurities) • Trace-element experiments (JET, AUG) • Post mortem SIMS measurements of wall tiles • Detailed PWI simulations w/ 3D MC transport codes • atomistic modelling of chemical effects and low-energy interactions with MD Courtesy of D. Borodin

  43. ITER divertor test platform (DTP2) in Tampere !! • VTT ja TTY host the ITER DTP2 facility • First (DTP) full scale divertor cassettes arrived early 2007 • DTP2 tests removing, transferring and exchanging the cassettes – all by remote control • DTP2 is crucial for successful operation of ITER: in the next 10-15 years all divertor maintenance procedures are tested and rehearsed at DTP2

  44. Summarizing… • The scientific feasibility of fusion energy has been proven on the ‘large’ JET and JT-60U tokamaks • Next step, ITER: a global project with the goal of verifying the technological feasibility of fusion energy • ITER = thusfar the most challenging technology project mankind has embarked on • ITER = driver for technological innovations and spin-offs • Parallel to ITER strong materials research is needed: DEMO and commercial fusion power plants need special materials • Fusion could be a real alternative for base line power production by the end of this century – when it is really needed • Finland (Association Euratom-Tekes) is disproportionately active in European fusion program…

  45. Question time Thank you for your attention! The average cruising airspeed velocity of an unladen European Swallow is roughly 11 meters per second, or 24 miles an hour.† The four capitals of Assyria were Ashur (or Qalat Sherqat), Calah (or Nimrud), the short-lived Dur Sharrukin (or Khorsabad), and Nineveh.† † http://www.style.org/unladenswallow/

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