Fusion

NUCLEAR Fusion

1. NUCLEAR FUSION ‘The holy grail of the energy world’ Presented by Mr. Shenoy Anush

2. What is energy? Energy is the ability of a physical system to do work. Where does energy come from? Sun, wind, tides, coal, oil, gas, fusion, fission, etc.. INTRODUCTION

3. Why is this energy needed? % Energy consumption by different sectors

4. While the population has tripled in the last 80 years, energy consumption has increased almost 6 times!

5. Electricity generation in Power plants From fossil fuels (88%) From hydro energy(6%) From other renewable sources (0.3%) Nuclear energy (5.7%) Electricity

6. The energy requirements for the 21 st century assuming that (a) mankind doesn’t act on global warming (b) mankind acts on global warming. (a) ( b)

7. Nuclear energy is the potential energy of the particles inside an atomic nucleus. Nuclear binding energy is the energy required to split a nucleus of an atom into its individual protons and neutrons. It is equivalent to the energy an atom releases when it is split. NUCLEAR ENERGY

8. Fission Heavy nuclei release energy when they split. The product nuclei weigh less than the original nucleus. Fusion Light nuclei like hydrogen & helium release energy when they fuse. The product nuclei weigh less than the parent nuclei. TYPES

9. The loss of mass in a nuclear reaction is known as MASS DEFECT denoted by ‘m’. This ‘mass defect’ is converted into energy as E=mc 2 MASS DEFECT

10. Why can energy can be generated by both joining of two nuclei and splitting of the nucleus? The explanation lies in the size of the nuclei. Light elements such as hydrogen have small nuclei that release lots of energy when they join together. Moving to heavier atoms, less energy is released in each fusion event, until, at iron no more energy is released by fusion. Any bigger, it takes energy to make the fusion happen. Atoms with really huge nuclei, such as uranium do the opposite of fusion. They release energy when they break apart.. PARADOX

11. GRAPH OF BINDING ENERGY v/s ATOMIC MASS

12. Seeing is believing! POWER OF NUCLEAR ENERGY! THE SUN

13. Nuclear fission is the process of splitting a heavy nucleus releasing energy and neutrons in the process. These neutrons when captured by another unstable nucleus, causes fission in it as well leading to a chain reaction. If the fission reaction is releasing more neutrons than it absorbs it is referred to as a self-sustaining chain reaction. NUCLEAR FISSION

14. Fission reactions are complex. Uranium-235 can break apart a number of different ways, and many of the atoms produced are unstable and radioactive: U 235 + neutron  2 neutrons + Kr 92 + Ba 142 + ENERGY U 235 + neutron  2 neutrons + Sr 92 + Xe 140 + ENERGY

15. SCHEMATICS OF A NUCLEAR FISSION CHAIN REACTION A uranium-235 atom absorbs a neutron and fissions into two new fission fragments, releasing three new neutrons and some binding energy. One of those neutrons is absorbed by an atom of uranium-238 and does not continue the reaction. Another neutron is simply lost and does not collide with anything, discontinuing the reaction. But, one neutron does collide with an atom of uranium-235, which then fissions and releases two neutrons and some binding energy. Both of those neutrons collide with uranium-235 atoms, each of which fissions and releases between one and three neutrons, which can then continue the reaction.

16. Radiation Radioactive wastes Raw material unavailability Uncontrolled reaction THE CONS

17. FUKUSHIMA DAIICHI INCIDENT 11 th March 2011

18. Nuclear fusion involves joining of smaller nuclei to form a larger nucleus and giving out a large amount of energy in the reaction. In the picture alongside, two isotopes of hydrogen, deuterium and tritium, combine to form a helium atom, releasing a neutron and a large amount of energy. Nuclear Fusion (brief)

19. The idea of fusion is literally to put ‘sun in a box’. But the problem is how to make the box? The vessel in which the fusion takes place has to withstand temperatures in excess of 100000000 C. Fusion occurs in celestial bodies like stars.

20. TRITIUM: Tritium is an isotope of hydrogen, which has two neutrons. It does not occur naturally. It can however be easily produced form the neutron bombardment of lithium, which is naturally abundant. Currently accessible reserves of lithium could supply all the world’s energy demands for more than 1000 years. DEUTERIUM: Deuterium is an isotope of hydrogen, which has one neutron. Its abundance is approximately 33 g of deuterium in every cubic meter of water. As water is available aplenty, we have a whole lot of deuterium. RAW MATERIALS FOR FUSION

21. Raw material Definition Natural occurrence Nature of the byproducts   Conditions   Energy Requirement   Energy Released Nuclear weapon FISSION V/S FUSION

22. Why fusion research ? Ever increasing energy demand. Limited fossil fuels. Global climate change. Limited scope of renewable energy. High energy output by fusion. NUCLEAR FUSION

23. COMPARISON OF FUSION AND FISSION OUTPUT

24. Collision of the charged nuclei. Overcoming the electrostatic repulsion. High kinetic energy Heat & electro-magnetic fields. Plasma ACHIEVING THE FUSION

25. Why is the energy released? Mass defect E=mc 2 Conditions for fusion Fuel Temperature Density Time

26. Fusion product Combination of three parameters – temperature, density and time Q-factor Important terms

27. Sun in a box problem! Two ways of confining Fusion: Inertial confinement fusion - ICF: Increase density of fusion plasma. Magnetically confined plasmas: Increase confinement time & plasma speed. Different Ways of Fusion

28. Inertial Confinement Fusion Concept

29. Before compression and ignition Density : solid DT ice at 0.225 g/cm 3 and gas Temperature : few Kelvin During the burn phase Density : 300 to 1000 times liquid density 300 to 1000 g/cm 3 ≈ 10 26 cm -3 Temperature : around 10.000.000 K or 10 keV Pressure : around 10 12 bar Confinement time needed : around 200 pico seconds Plasma Conditions During ICF

30. Compare Driver to Target Sizes ! real NIF target Computer Generated Schematics DT capsule

31. National Ignition Facility (NIF, Livermore, USA) ► Record 1.875 million joule pulse of ultraviolet laser light to the target chamber on March 15, 2012 Laser Mega-Joule (LMJ, France) ► Commissioning (full scale) in 2011 FIREX I and FIREX II (ILE, Osaka, Japan) ► Fast ignition experiments showed prove-of-principle ► Fully integrated experiments in 2010 / 2011 HiPER project (Europe, R.A.L. ???) ► European fast ignition proposal based on NIF ► Design work funded last year; full funding pending Interesting Experiments in ICF

32. High Power laser Energy Research facility  ( HiPER ), is a proposed experimental laser-driven inertial confinement fusion (ICF) device undergoing preliminary design for possible construction in the European Union. HiPER is the first experiment designed specifically to study the "fast ignition" approach to generating nuclear fusion

33. Magnetic Confinement Magnetic confinement uses magnetic and electric fields to heat and squeeze the hydrogen plasma.

34. Microwaves, electricity and neutral particle beams from accelerators heat a stream of hydrogen gas. This heating turns the gas into plasma. This plasma gets squeezed by super-conducting magnets, thereby allowing fusion to occur. How Does It Work?

35. The most efficient shape for the magnetically confined plasma is a donut shape (toroid). A reactor of this shape is called a tokamak " Tokamak " is a Russian acronym for " toroidal chamber with axial magnetic field Tokmak

36. The ITER tokamak will be a self-contained reactor whose parts are in sections. These sections can be easily inserted and removed without having to tear down the entire reactor for maintenance. The tokamak will have a plasma toroid with a 2-meter inner radius and a 6.2-meter outer radius.

37. The fusion reactor will heat a stream of deuterium and tritium fuel to form high-temperature plasma. It will squeeze the plasma so that fusion can take place. The lithium blankets outside the plasma reaction chamber will absorb high-energy neutrons from the fusion reaction to make more tritium fuel. The blankets will also get heated by the neutrons. The heat will be transferred by a water-cooling loop to a heat exchanger to make steam. The steam will drive electrical turbines to produce electricity. The steam will be condensed back into water to absorb more heat from the reactor in the heat exchanger. Working of a fusion reactor

38. Flow diagram of fusion process

39. Joint European Torus JET or the Joint European Torus, is a magnetic confinement plasma physics experiment located in Oxfordshire, UK . Its main purpose is to open the way to nuclear fusion experimental tokamak reactors such as ITER and DEMO.

40. JET investigates the potential of fusion power as a safe, clean, and virtually limitless energy source for future generations. The largest tokamak in the world, it is the only operational fusion experiment capable of producing fusion energy. JET is collectively used by many laboratories, scientists and engineers.

41. TIMELINE OF JET DATE EVENT 1973 Beginning of design work 1977 Culham site is chosen and the construction work begins 25th June 1983 Very first plasma achieved at JET 9th April 1984 JET officially opened by Her Majesty Queen Elizabeth II 9th November 1991 The world’s first controlled release of fusion energy 1993 JET converted to diverter configuration 1997 JET produces 16 megawatts of fusion power 1998 Remote Handling first used for in-vessel work 2000 The collective use of JET and its scientific programme becomes managed through the European Fusion Development Agreement (EFDA) 2006 JET starts operation with ITER-like magnetic configurations 2009-2011 Installation of the ITER-Like Wall

42. Weight of the toroidal field coils: 384 tonne Weight of the iron core: 2800 tonnes Weight of the vacuum vessel: 100 tonnes. Wall material: Entirely Beryllium save Tungsten 'exhaust' Plasma major radius: 2.96 m Plasma minor radius: 2.10 m (vertical), 1.25 m (horizontal) Currently the JET is shut down for maintenance and upgradation purposes. Technical specifications :

43. International Thermonuclear Experimental Reactor, ITER is a nuclear fusion research project established on 24 th October, 2007. Currently the world’s largest and most advanced experimental tokamak nuclear fusion reactor at its Cadarache headquarters in France. The ITER project aims to make the long-awaited transition from theoretical studies of plasma physics to fullscale electricity producing fusion power plants. The project is funded and run by its member entities : European Union, India , Japan, China, Russia, South Korea and The United States. Website: www.iter.org

44. To momentarily produce a Q value of 10. To produce steady-state plasma with a Q value greater than 5. To maintain a fusion pulse for up to 480 seconds. To ignite a self-sustaining plasma. To develop technologies and processes needed for a fusion power plant including superconducting magnets and remote handling. To verify tritium breeding concepts. To refine neutron shield/heat conversion technology. ITER GOALS

45. TIMELINE OF EVENTS Date Event November 2006 Participants agreed to fund the creation of the reactor. 2008 Site preparation start. 2009 Site preparation completion. 2010 Tokamak complex excavation start. 2011 Tokamak complex construction start. 2015 Predicted: Tokamak assembly start. 2018 Predicted: Tokamak assembly completion, start torus pump down. November 2019 Predicted: Achievement of first plasma. 2026 Predicted: Start of deuterium-tritium operation. 2038 Predicted: End of project.

46. Demonstration Power Plant, DEMO will be constructed once designs which solve the many problems of current fusion reactors are engineered. These problems include : containing the plasma fuel at high temperatures maintaining a great enough density of reacting ions capturing high-energy neutrons from the reaction without melting the walls of the reactor. DEMO

47. While ITER's goal is to produce 10 times as much power as is required for breakeven, DEMO's goal is to produce 25 times as much power. Where ITER's goal is to produce 500 megawatts of fusion power for at least 500 seconds, the goal of DEMO will be to produce at least four times that much fusion power on a continual basis. DEMO's 2-4 gigawatts of power output will be on the scale of a modern electric power plant. DEMO is intended to be the first fusion reactor to generate electrical power. Goals of DEMO

48. Prototype power plant, PROTO is a beyond DEMO experiment. PROTO would act as a prototype power station, taking in any remaining technology refinements, and demonstrating electricity generation on a commercial basis. PROTO is only expected after DEMO, ie a post-2050 timeline. If it happens, it would make PROTO the first commercial nuclear fusion power plant in the world. PROTO

49. The price tag of ITER alone is € 15 billion. Nuclear fusion R&D will need further promotion totalling around € 60-80 billion over a period of 50 year. On the other hand: The annual R&D budget of Beyond Petroleum was 450 Million Euro in 2009 Europe’s contribution to Fusion research is less than 1% of the total money spent by it on oil alone ECONOMICS

50. This initial investment will be worthwhile if fusion will turn out to be an economical way to generate power. Having negligible negative impact to the nature, Fusion promises to be the answer to our energy crisis. Conclusion

51. Indeed nuclear fusion is ‘Energy in our hands’ THANK YOU